37 results on '"Bossoni S"'
Search Results
2. Reciprocal relationship between the level of circulating cortisol and growth hormone secretion in response to growth hormone-releasing hormone in man: studies in patients with adrenal insufficiency.
- Author
-
Giustina A, Bresciani E, Bossoni S, Chiesa L, Misitano V, Wehrenberg WB, and Veldhuis JD
- Subjects
- Addison Disease pathology, Addison Disease physiopathology, Adrenal Gland Diseases pathology, Adrenal Gland Diseases physiopathology, Adult, Aged, Body Mass Index, Female, Growth Hormone-Releasing Hormone administration & dosage, Humans, Injections, Intravenous, Male, Middle Aged, Addison Disease blood, Adrenal Gland Diseases blood, Growth Hormone blood, Growth Hormone-Releasing Hormone pharmacology, Hydrocortisone blood
- Abstract
The aim of our study was to elucidate the relationship between the level of circulating cortisol and the GH responsiveness to GHRH in six hypoadrenal patients (one male and five females; age range, 35-67 yr; body mass index range, 18-31 kg/m2). Twenty-four hours after taking the last dose of replacement therapy, each patient underwent the following experimental trials on nonconsecutive days: 1) saline, and 2) 12.5 mg, or 3) 25 mg, or 4) 250 mg hydrocortisone hemisuccinate in 250 mL saline constant iv infusion from 0-180 min. On each occasion, 1 micrograms/kg human GHRH-(1-29)NH2 was injected as an iv bolus at 60 min. During GHRH and saline infusion, serum cortisol levels were always less than the detection limit of the assay (55 nmol/L). During 12.5-, 25-, and 250-mg hydrocortisone infusions (from 15-180 min), serum cortisol averaged 413.8 +/- 19.3, 772.5 +/- 46.9, and 1520.2 +/- 110.4 nmol/L, respectively. The GH peaks after GHRH treatment during the various infusions of hydrocortisone were compared to the GH peaks observed after saline, which were normalized to 100% in each subject. GH peaks after GHRH and 25 mg hydrocortisone (70 +/- 11%) and GHRH and 250 mg hydrocortisone (69 +/- 7%) were significantly (P < 0.05) lower than the GH peaks after GHRH and saline or GHRH and 12.5 mg hydrocortisone (83 +/- 15%). No significant differences were observed between the GH peaks after GHRH and 12.5 mg hydrocortisone or GHRH and saline. Our data demonstrate that in hypoadrenal patients, the acute absence of circulating cortisol does not impair the GH secretory response to GHRH with respect to the eucortisolemic state. Moreover, our data suggest that 700 nmol/L is the approximate threshold serum cortisol concentration above which a decrease in the GH responsiveness to GHRH is observed in humans. Further increases in serum cortisol levels above this threshold value do not cause a proportional decrease in the GH responsiveness to GHRH.
- Published
- 1994
- Full Text
- View/download PDF
3. Effects of metoclopramide on the paradoxical growth hormone response to galanin in acromegaly.
- Author
-
Giustina A, Doga M, Bodini C, Bossoni S, Bresciani E, and Bussi AR
- Subjects
- Acromegaly metabolism, Adult, Aged, Body Mass Index, Female, Galanin, Growth Hormone metabolism, Humans, Infusions, Intravenous, Male, Metoclopramide administration & dosage, Middle Aged, Peptides administration & dosage, Pituitary Gland metabolism, Radioimmunoassay, Time Factors, Acromegaly blood, Growth Hormone blood, Metoclopramide pharmacology, Peptides pharmacology
- Abstract
Galanin is able to enhance growth hormone (GH)-releasing hormone stimulated GH secretion in normal man. In acromegaly circulating GH levels are elevated and the GH response to GHRH may be exaggerated. Galanin has been recently shown to decrease circulating GH levels in acromegaly. Dopaminergic drugs were the only previously known agents able to cause a paradoxical GH fall in acromegaly. Aim of our study was to investigate the effects of a potent central dopaminergic receptor blocker, metoclopramide (MCP), on the galanin-induced paradoxical GH secretion in acromegalic subjects. Two male and three female patients with active acromegaly (age range 44-66 years, body mass index range 24.6-28 Kg/m2) were studied after 45 min i.v. infusion of porcine galanin (0.5 mg in 100 ml of saline) from 0 to 45 min combined with a 60 min i.v. infusion of a) saline (100 ml) or b) MCP (10 mg in 100 ml of saline) from -15 to 45 min. After galanin, GH values fell from baseline (27.5 +/- 10 micrograms/L) to a mean nadir of 16.4 +/- 6.1 micrograms/L; after galanin + MCP, circulating GH levels were also decreased (mean nadir 17.3 +/- 8.1 micrograms/L) in all the patients with respect to baseline (23.6 +/- 9.7 micrograms/L). No significant differences were found in absolute or percent of baseline GH levels after galanin+saline vs galanin + MCP. Our results suggest that the paradoxical GH fall after galanin in acromegalic patients is not mediated through dopaminergic receptor. It can be hypothesized that galanin may interact at the pituitary level with its own receptors expressed by GH-secreting adenomatous cells.
- Published
- 1993
- Full Text
- View/download PDF
4. Variability in the growth hormone response to growth hormone-releasing hormone alone or combined with pyridostigmine in type 1 diabetic patients.
- Author
-
Giustina A, Bodini C, Bossoni S, Valentini U, and Wehrenberg WB
- Subjects
- Adult, Blood Glucose metabolism, Female, Humans, Individuality, Male, Single-Blind Method, Diabetes Mellitus, Type 1 metabolism, Growth Hormone blood, Growth Hormone pharmacology, Pyridostigmine Bromide pharmacology
- Abstract
In man the GH response to GHRH is variable within and between subjects. Pyridostigmine (PD), an acetylcholinesterase inhibitor, has been shown to reduce the variability of the GH response to GHRH in normal subjects. The aim of this study was to assess the existence of either inter- or intraindividual variability in the GH response to GHRH in type 1 diabetic patients. Moreover, we investigated the effect of PD on such variability in the same patients. Seven (4 females-3 males) nonobese type 1 diabetic patients underwent two experiments performed in consecutive days according to a single-blind protocol: 1) 120 mg oral PD 60 min before iv injection of human (h) GHRH-(1-29) NH2, 100 micrograms in 2 ml of sterile water; 2) oral placebo 60 min before iv injection of 100 micrograms hGHRH. The two experiments were then repeated, following the same procedure, one and two weeks after the start of the study. The GH peaks after GHRH were variable within different subjects but also in the same subject on different occasions. However, the mean GH peak levels after GHRH in the three tests were not significantly different (14.2 +/- 3.5, 15.3 +/- 3, 16.5 +/- 6.4 micrograms/L, respectively), the coefficient of variation for each test was 65%, 51.8%, 102.4%, respectively (mean 73.1 +/- 15.1%). The GH response to GHRH was always significantly enhanced by PD administration: the mean GH peak levels in the three tests were 31.9 +/- 7.1, 44.8 +/- 10.4, 49.9 +/- 13.1 micrograms/L, respectively, without significant differences between tests.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1993
- Full Text
- View/download PDF
5. Arginine blocks the inhibitory effect of hydrocortisone on circulating growth hormone levels in patients with acromegaly.
- Author
-
Giustina A, Schettino M, Bossoni S, Bussi AR, Doga M, Licini M, and Wehrenberg WB
- Subjects
- Adult, Drug Combinations, Female, Growth Hormone blood, Humans, Infusions, Intravenous, Male, Middle Aged, Time Factors, Acromegaly blood, Arginine pharmacology, Growth Hormone adverse effects, Hydrocortisone pharmacology
- Abstract
In patients with acromegaly, circulating growth hormone (GH) levels and GH responses to GH-releasing hormone (GHRH) are decreased by long-term administration of pharmacological doses of glucocorticoids. The aim of our study was to investigate the acute effects of intravenous (i.v.) infusion of hydrocortisone combined either with saline or arginine infusion on circulating GH levels in acromegaly. We studied five adult patients with acromegaly, two men and three women aged 54.6 +/- 4 years having a body mass index of 25.9 +/- 1.2 kg/m2. On two randomized occasions, patients underwent a bolus i.v. injection of 100 mg hydrocortisone succinate at time 0 followed by a 120-minute i.v. infusion of 250 mg hydrocortisone in 250 mL saline, combined with a 90-minute (from -15 to 75 minutes) i.v. infusion of (1) 60 g arginine hydrochloride in 200 mL saline, or (2) 200 mL saline. In all of the acromegalic patients during the infusion of hydrocortisone alone, serum GH levels clearly decreased (nadir range, 26.4% to 68.1%) with respect to GH levels before hydrocortisone administration (mean of time -15 and 0, basal level), with a nadir between 90 and 180 minutes after the beginning of the infusion. After arginine pretreatment, GH levels were significantly enhanced compared with levels attained with hydrocortisone saline, and they were also significantly increased (peak, 167.5% +/- 27.7%) with respect to basal levels. Our data show that arginine blocks the inhibitory effect of acute and sustained hypercortisolism on circulating GH levels in acromegaly.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1993
- Full Text
- View/download PDF
6. Effect of galanin on the growth hormone (GH) response to GH-releasing hormone in patients with Cushing's disease.
- Author
-
Giustina A, Bossoni S, Bussi AR, Pozzi A, and Wehrenberg WB
- Subjects
- Adenoma complications, Adult, Analysis of Variance, Cushing Syndrome etiology, Cushing Syndrome metabolism, Female, Galanin, Humans, Middle Aged, Pituitary Neoplasms complications, Single-Blind Method, Time Factors, Cushing Syndrome drug therapy, Growth Hormone biosynthesis, Growth Hormone-Releasing Hormone pharmacology, Neuropeptides therapeutic use, Peptides therapeutic use
- Abstract
Attenuated plasma GH secretion during sleep and blunted GH responses to provocative stimuli have been observed in patients with Cushing's disease. Synthetic porcine galanin elicits GH secretion when given alone, and enhances the GH response to GHRH in normal human subjects. The aim of our study was to investigate the effects of galanin on the GH response to GHRH in patients with Cushing's disease. We studied 5 female subjects with untreated active Cushing's disease caused by micro-pituitary adenomas (age 43 +/- 6.7 years; BMI 30 +/- 0.7 kg/m2). Four normal adult females, matched for age and body weight with the patients with Cushing's disease, were studied as controls. Subjects underwent in random order: (1) infusion of synthetic porcine galanin IV, 500 micrograms in 100 mL; (2) infusion of saline, IV, 100 mL. A bolus of human GHRH(1-29)NH2 (Geref, Serono, Italy), 100 micrograms in 1 mL saline, was injected IV at 0 minutes. Patients with Cushing's disease showed blunted GH peaks after GHRH (1.2 +/- 0.4 micrograms/L) during saline infusion, as compared to normal controls (24.6 +/- 4.6 micrograms/L; p < 0.05). During galanin infusion a significantly enhanced GH response to GHRH, as compared with saline infusion, was observed in control subjects (GH peak: 51.4 +/- 9.8 micrograms/L; p < 0.05), but not in patients with Cushing's disease (GH peak: 2.3 +/- 0.6 micrograms/L). GH levels were significantly lower both after saline and after galanin in patients with Cushing's disease as compared to normal controls. Our data demonstrate that galanin is not able to enhance the GH response to GHRH in patients with Cushing's disease. That galanin cannot reverse this effect suggests that the mechanism of action of galanin is not via a decrease in somatostatin release by the hypothalamus.
- Published
- 1993
- Full Text
- View/download PDF
7. Galanin does not affect the growth hormone-releasing hormone-stimulated growth hormone secretion in patients with hyperthyroidism.
- Author
-
Giustina A, Bussi AR, Legati F, Bossoni S, Licini M, Schettino M, Zuccato F, and Wehrenberg WB
- Subjects
- Adult, Aged, Female, Galanin, Graves Disease blood, Growth Hormone metabolism, Humans, Male, Middle Aged, Pituitary Gland metabolism, Growth Hormone blood, Growth Hormone-Releasing Hormone pharmacology, Hyperthyroidism blood, Peptides pharmacology
- Abstract
Patients with hyperthyroidism have reduced spontaneous and stimulated growth hormone (GH) secretion. The aim of our study was to evaluate the effects of galanin, a novel neuropeptide which stimulates GH secretion in man, on the GH response to GHRH in patients with hyperthyroidism. Eight untreated hyperthyroid patients with Graves' disease (6F, 2M, aged 25-50 years) and six healthy volunteers (3F, 3M, aged 27-76 years) underwent from -10 to 30 min in random order: (i) porcine galanin, iv, 500 micrograms in 100 ml saline; or (ii) saline, iv, 100 ml. A bolus of human GHRH(1-29)NH2, 100 micrograms, was injected iv at 0 min. Hyperthyroid patients showed blunted GH peaks after GHRH+saline (10.2 +/- 2.5 micrograms/l) compared to normal subjects (20.7 +/- 4.8 micrograms/l, p < 0.05). GH peaks after GHRH+galanin were also significantly lower in hyperthyroid subjects (12.5 +/- 3 micrograms/l) compared to normal subjects (43.8 +/- 6 micrograms/l, p < 0.05). That galanin is not able to reverse the blunted GH response to GHRH in hyperthyroidism suggests that hyperthyroxinemia may either increase the somatostatin release by the hypothalamus or directly affect the pituitary GH secretory capacity.
- Published
- 1992
- Full Text
- View/download PDF
8. Arginine normalizes the growth hormone (GH) response to GH-releasing hormone in adult patients receiving chronic daily immunosuppressive glucocorticoid therapy.
- Author
-
Giustina A, Bossoni S, Bodini C, Girelli A, Balestrieri GP, Pizzocolo G, and Wehrenberg WB
- Subjects
- Adult, Female, Growth Hormone blood, Humans, Kinetics, Male, Radioimmunoassay, Reference Values, Time Factors, Arginine pharmacology, Growth Hormone metabolism, Growth Hormone-Releasing Hormone pharmacology, Immunosuppression Therapy, Prednisone therapeutic use
- Abstract
Glucocorticoids are thought to inhibit GH secretion through an enhancement of endogenous somatostatin tone. The aim of our study was to evaluate the effect of arginine, a secretagogue that increases GH secretion acting at the hypothalamic level, probably by decreasing somatostatin tone, on GH-releasing hormone (GHRH)-induced GH secretion in three male and five female adult patients with nonendocrine disease who were receiving daily immunosuppressive glucocorticoid therapy. Six normal subjects (four males and two females) served as controls. GHRH-induced GH secretion was evaluated after 30-min iv infusion of saline (100 mL) or arginine (30 g) in 100 mL saline. After saline administration, steroid-treated patients showed a blunted GH response to GHRH (GH peak, 8.7 +/- 2.4 micrograms/L) compared to that of normal subjects (GH peak, 23.8 +/- 3.9 micrograms/L). The GH responses to GHRH increased (P less than 0.05) after pretreatment with arginine compared to saline pretreatment in both normal subjects (GH peak, 36.6 +/- 4.0 micrograms/L) and steroid-treated patients (GH peak, 28.4 +/- 5.5 micrograms/L). The GH responses to GHRH plus arginine were not significantly different in steroid-treated and normal subjects. Thus, arginine is able to normalize the GH response to GHRH in patients receiving chronic glucocorticoid treatment. Our data are evidence that the stimulatory action of arginine and the inhibitory action of glucocorticoids on GH secretion are mediated by opposite effects on hypothalamic somatostatin tone.
- Published
- 1992
- Full Text
- View/download PDF
9. Effect of galanin on growth hormone-releasing hormone-stimulated growth hormone secretion in adult patients with nonendocrine diseases on long-term daily glucocorticoid treatment.
- Author
-
Giustina A, Girelli A, Bossoni S, Legati F, Schettino M, and Wehrenberg WB
- Subjects
- Adult, Drug Administration Schedule, Female, Galanin, Glucocorticoids administration & dosage, Growth Hormone blood, Humans, Kinetics, Male, Middle Aged, Neurotransmitter Agents pharmacology, Glucocorticoids therapeutic use, Growth Hormone metabolism, Growth Hormone-Releasing Hormone pharmacology, Peptides pharmacology
- Abstract
Glucocorticoids are thought to inhibit growth hormone (GH) secretion through an enhancement of endogenous somatostatin tone. The aim of our study was to evaluate the effect of galanin, a neuropeptide that stimulates GH secretion, on GH-releasing hormone (GHRH)-induced GH secretion in adult patients with nonendocrine diseases who were under daily immunosuppressive glucocorticoid therapy. Six normal subjects (four men, two women) and seven steroid-treated subjects (three men, four women) were studied. GHRH-induced GH secretion was evaluated during a 40-minute intravenous (i.v.) infusion of saline or porcine galanin (12.5 micrograms/min). During saline infusion, steroid-treated patients showed a blunted GH response to GHRH (GH peak, 8.1 +/- 2.8 micrograms/L), as compared with normal subjects (GH peak, 23.8 +/- 3.9 micrograms/L). During galanin infusion, the GH response to GHRH was significantly enhanced (GH peak, 46.6 +/- 9.4 micrograms/L, P less than .05), as compared with saline infusion in normal subjects. In contrast, galanin infusion did not enhance the GH response to GHRH (GH peak, 16.6 +/- 6.5 micrograms/L), as compared with saline infusion in steroid-treated patients. The area under the GH-response curves was also significantly (P less than .05) lower in steroid-treated subjects, as compared with normal subjects. Thus, galanin failed to normalize or enhance the GH response to GHRH in patients treated long-term with glucocorticoids. It can be hypothesized that galanin does not elicit GH secretion by decreasing hypothalamic somatostatin tone.
- Published
- 1992
- Full Text
- View/download PDF
10. Effects of pyridostigmine on spontaneous and growth hormone-releasing hormone stimulated growth hormone secretion in children on daily glucocorticoid therapy after liver transplantation.
- Author
-
Giustina A, Girelli A, Alberti D, Bossoni S, Buzi F, Doga M, Schettino M, and Wehrenberg WB
- Subjects
- Child, Child, Preschool, Cyclosporine therapeutic use, Female, Humans, Hypothalamus drug effects, Male, Prednisolone therapeutic use, Single-Blind Method, Growth Hormone metabolism, Growth Hormone-Releasing Hormone pharmacology, Hypothalamus metabolism, Liver Transplantation physiology, Pyridostigmine Bromide pharmacology
- Abstract
Objectives: We aimed to investigate both nocturnal spontaneous and morning growth hormone (GH)-releasing hormone (GHRH)-induced GH secretion in children on daily glucocorticoid treatment after liver transplantation and to evaluate the effect of pyridostigmine (an acetylcholinesterase inhibitor thought to reduce hypothalamic somatostatin tone) on GH secretion in these patients., Design: We performed a randomized, single-blind, cross-over study., Patients: We studied three male and three female juvenile patients, within a year of orthotopic liver transplantation and under immunosuppressive glucocorticoid therapy (mean dose +/- SEM, 5.92 +/- 0.63 mg/day) and five normal children (four males, one female)., Measurements: Both nocturnal spontaneous and morning GHRH-induced GH secretion were evaluated after administration of placebo, 1 tablet p.o., or pyridostigmine, 2 mg/kg p.o., Results: Spontaneous GH. Placebo: in liver transplanted children nocturnal GH secretion (mean GH level 10.8 +/- 2.0 mU/l) was not significantly different with respect to normal children (mean GH level 12.8 +/- 1.2 mU/l); pyridostigmine: nocturnal GH secretion was significantly increased as compared to placebo in subjects with liver transplantation but not in normal children. GHRH test. Placebo: liver transplanted patients showed a blunted GH response to GHRH with respect to normal children; pyridostigmine: the GH responses to GHRH (P less than 0.05) increased as compared to placebo and did not differ significantly in the two groups., Conclusions: Our data suggest a steroid-mediated increase in hypothalamic somatostatin tone in liver transplanted children.
- Published
- 1991
- Full Text
- View/download PDF
11. Effects of exogenous growth hormone pretreatment on the pituitary growth hormone response to growth hormone-releasing hormone alone or in combination with pyridostigmine in type I diabetic patients.
- Author
-
Giustina A, Bossoni S, Bodini C, Cimino A, Pizzocolo G, Schettino M, and Wehrenberg WB
- Subjects
- Administration, Oral, Adolescent, Adult, Diabetes Mellitus, Type 1 blood, Double-Blind Method, Drug Therapy, Combination, Female, Growth Hormone administration & dosage, Growth Hormone-Releasing Hormone administration & dosage, Humans, Injections, Intravenous, Male, Middle Aged, Pyridostigmine Bromide administration & dosage, Diabetes Mellitus, Type 1 drug therapy, Growth Hormone blood, Growth Hormone therapeutic use, Growth Hormone-Releasing Hormone therapeutic use, Pyridostigmine Bromide therapeutic use
- Abstract
We evaluated the effects of iv pretreatment with exogenous GH on the GH response to GHRH either alone or in combination with pyridostigmine in 14 Type I diabetic patients and 6 normal subjects. All the subjects received an iv bolus injection of biosynthetic human GH, 2 IU; 2 h later they received either a. pyridostigmine, 120 mg orally, or b. placebo, 2 tablets orally, followed 1 h later by iv injection of GHRH(1-29) NH2, 100 micrograms. In normal subjects the median GH peak after GH+ GHRH was 1.8, range 1.2-6.9 micrograms/l. Pyridostigmine enhanced the GH response to GHRH in all subjects. The median GH peak after pyridostigmine + GH + GHRH was 32.7, range 19.8-42.1 micrograms/l (p less than 0.001 vs GHRH alone). Seven diabetic subjects had median GH peaks after GH + GHRH greater than 6.9 micrograms/l (the maximum GH peak after GH + GHRH in normal subjects) (group A: median GH peak 35.7, range 21.7-55 micrograms/l). The other diabetic subjects had GH peak lower than 6.9 micrograms/l (group B: median GH peak 4.4, range 2.1-6.5 micrograms/l). Pyridostigmine significantly increased the GH response to GHRH in group B patients (median GH peak 29.3, range 15.7-93.4 micrograms/l, p less than 0.001 vs GH + GHRH alone), but not in group A patients (median GH peak 39.9, range 21.9-64.9 micrograms/l). Group A diabetic patients were younger and had higher HbA1c and blood glucose levels than group B patients. In those diabetic patients with an exaggerated GH response to GH + GHRH, pyridostigmine failed to cause the increase in GH secretion observed in diabetic and control subjects with no responses to GH + GHRH.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1991
- Full Text
- View/download PDF
12. The role of cholinergic tone in modulating the growth hormone response to growth hormone-releasing hormone in normal man.
- Author
-
Giustina A, Bossoni S, Bodini C, Doga M, Girelli A, Buffoli MG, Schettino M, and Wehrenberg WB
- Subjects
- Adult, Dose-Response Relationship, Drug, Female, Growth Hormone blood, Humans, Male, Placebos, Pyridostigmine Bromide pharmacology, Reference Values, Growth Hormone metabolism, Growth Hormone-Releasing Hormone pharmacology, Parasympathetic Nervous System physiology
- Abstract
Growth hormone-releasing hormone (GHRH) increases serum GH levels in a dose-dependent manner. Pyridostigmine (PD), an acetylcholinesterase inhibitor, is able to elicit GH secretion when administered alone and to enhance the GH response to GHRH in normal subjects, probably via a decrease in the hypothalamic release of somatostatin. The aim of the present study was to investigate if an enhancement of the cholinergic tone was able to influence the dose-response relationship between GHRH and GH in normal adult subjects. Six healthy adult volunteers underwent 10 experimental protocols. They were: human GHRH (1-29)NH2, 1 micrograms/kg injected as an intravenous (IV) bolus 60 minutes after (a) PD, 120 mg administered orally, or (b) placebo, two tablets administered orally; GHRH, 0.3 micrograms/kg injected as an IV bolus 60 minutes after (c) PD or (d) placebo; GHRH, 0.1 micrograms/kg injected as an IV bolus 60 minutes after (e) PD or (f) placebo; GHRH, 0.01 micrograms/kg injected as an IV bolus 60 minutes after (g) PD or (h) placebo; saline, 1 mL injected as an IV bolus 60 minutes after (i) PD or (l) placebo. The GH response in placebo-treated subjects was similar after 1 microgram/kg and 0.3 microgram/kg GHRH, while the 0.1 microgram/kg dose elicited a lower response. The 0.01 microgram/kg dose of GHRH did not significantly increase GH levels as compared with saline. After PD, the GH responses to GHRH were greatly enhanced at all doses tested: 1.0, 0.3, and 0.1 microgram/kg GHRH all elicited similar GH responses; the GH response to 0.01 microgram/kg GHRH was lower, but was still higher than that observed after saline.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1991
- Full Text
- View/download PDF
13. Pyridostigmine enhances even if it does not normalize the growth hormone responses to growth hormone-releasing hormone in patients with Cushing's disease.
- Author
-
Giustina A, Bossoni S, Bodini C, Ferrari C, Pizzocolo G, Scalvini T, Schettino M, and Wehrenberg WB
- Subjects
- Adenoma blood, Administration, Oral, Adult, Antibodies, Monoclonal, Cushing Syndrome blood, Cushing Syndrome etiology, Female, Growth Hormone blood, Humans, Injections, Intravenous, Pituitary Neoplasms blood, Radioimmunoassay, Adenoma physiopathology, Cushing Syndrome physiopathology, Growth Hormone metabolism, Growth Hormone-Releasing Hormone administration & dosage, Pituitary Neoplasms physiopathology, Pyridostigmine Bromide administration & dosage
- Abstract
Subjects with Cushing's disease have diminished growth hormone (GH) response to growth hormone-releasing hormone (GHRH). The aim of our study was to investigate the underlying mechanism of this diminished GH response in these patients using pyridostigmine (PD), an acetylcholinesterase inhibitor, which is reported to increase GH secretion by reducing somatostatin tone. Eight subjects with untreated Cushing's disease (caused by a pituitary adenoma) and 6 control subjects received GHRH 100 micrograms in 1 ml of saline, as intravenous bolus injection 60 min after (1) placebo (2 tablets, p.o.) or (2) PD (120 mg, p.o.). After GHRH plus placebo, the GH peak (mean +/- SEM) was significantly lower in subjects with Cushing's disease (2.4 +/- 0.5 micrograms/l) compared to control subjects (25.1 +/- 1.8 micrograms/l, p less than 0.05). After GHRH plus PD, the GH peak was significantly enhanced both in subjects with Cushing's disease (7.1 +/- 2.3 micrograms/l, p less than 0.05) and in control subjects (42.3 +/- 4.3 micrograms/l, p less than 0.05). In patients with Cushing's disease, the GH response to GHRH plus PD was lower with respect to the GH response to GHRH alone in normal subjects. We conclude that hypercortisolism may cause a decrease in central cholinergic tone which is in turn hypothesized to be responsible of an enhanced somatostatin release from the hypothalamus. However, other metabolic or central nervous system alterations may act synergistically with hypercortisolism in causing GH inhibition in patients with Cushing's disease.
- Published
- 1991
- Full Text
- View/download PDF
14. Impaired growth hormone (GH) response to pyridostigmine in type 1 diabetic patients with exaggerated GH-releasing hormone-stimulated GH secretion.
- Author
-
Giustina A, Bossoni S, Cimino A, Pizzocolo G, Romanelli G, and Wehrenberg WB
- Subjects
- Adolescent, Adult, Cholinesterase Inhibitors, Drug Synergism, Female, Glycated Hemoglobin metabolism, Gonadotropin-Releasing Hormone administration & dosage, Humans, Kinetics, Male, Pyridostigmine Bromide administration & dosage, Diabetes Mellitus, Type 1 physiopathology, Gonadotropin-Releasing Hormone pharmacology, Growth Hormone metabolism, Pyridostigmine Bromide pharmacology
- Abstract
In the present study we investigated the effects of the acetylcholinesterase inhibitor pyridostigmine (PD), which is hypothesized to decrease hypothalamic somatostatin tone, alone and in association with GH-releasing hormone (GHRH) on GH secretion in 18 type 1 diabetic patients and 12 normal subjects using a randomized double blind placebo-controlled protocol. All subjects received either 120 mg oral PD or placebo 60 min before iv injection of either human GHRH-(1-29) NH2 (100 micrograms) or sterile water (2 mL). In normal subjects both PD alone and GHRH alone caused a significant increase in GH. PD and GHRH acted in a synergistic fashion when combined. In diabetic patients the GH response to GHRH was variable. To segregate the responses, the ratio between the GH increase after GHRH plus PD and after GHRH alone was calculated for each subject. In 10 diabetic patients (group A) the ratio was lower than 2 SD (P less than 0.05) from the mean response of normal subjects. These patients showed an exaggerated GH increase after GHRH and a lower GH increase after PD with respect to normal subjects. Eight diabetic patients (group B) showed a ratio similar to that in normal subjects and similar GH responses to the stimuli. No significant differences were found between groups A and B with respect to age, body mass index, and blood glucose levels. Duration of diabetes was longer and basal GH levels were higher in group A. Hemoglobin-A1c was higher in group A, but of only borderline statistical significance (P = 0.052). Our data demonstrate that in diabetic patients with exaggerated GH responses to GHRH an increase in cholinergic tone does not affect GH secretion. These data suggest that in some type 1 diabetic patients an altered somatostatinergic control of GH secretion may contribute to their abnormal GH response to GHRH.
- Published
- 1990
- Full Text
- View/download PDF
15. Pyridostigmine blocks the inhibitory effect of glucocorticoids on growth hormone-releasing hormone stimulated growth hormone secretion in normal man.
- Author
-
Giustina A, Girelli A, Doga M, Bodini C, Bossoni S, Romanelli G, and Wehrenberg WB
- Subjects
- Adult, Cortisone analogs & derivatives, Cortisone pharmacology, Female, Glucocorticoids administration & dosage, Glucocorticoids antagonists & inhibitors, Growth Hormone metabolism, Growth Hormone-Releasing Hormone antagonists & inhibitors, Humans, Hydrocortisone blood, Hypothalamus drug effects, Hypothalamus metabolism, Male, Pituitary Gland drug effects, Pituitary Gland metabolism, Glucocorticoids pharmacology, Growth Hormone blood, Growth Hormone-Releasing Hormone pharmacology, Pyridostigmine Bromide pharmacology
- Abstract
Glucocorticoids have been shown to inhibit GH secretion in normal man when acutely and chronically administered in pharmacological amounts. Pyridostigmine (PD), an acetylcholinesterase inhibitor, is able to elicit GH secretion when administered alone and to enhance the GH response to GHRH in normal subjects probably via a decrease in the hypothalamic release of somatostatin. The aim of the present study was to investigate the influence of glucocorticoids on the GH response to PD administered either alone or in combination with GHRH in normal adult subjects. Six healthy adult volunteers underwent six experimental protocols. They received 1) human (h) GHRH(1-29)NH2, 100 micrograms injected as an iv bolus; 2) cortisone acetate, 50 mg administered orally (po) 60 min before an hGHRH iv bolus injection; 3) PD, 120 mg administered po, 60 min before an hGHRH iv bolus injection; 4) PD and cortisone acetate, administered po 60 min before an hGHRH iv bolus injection; 5) PD, administered po 60 min before a saline iv bolus injection; 6) PD and cortisone acetate administered po 60 min before a saline iv bolus injection. Mean GH levels, peak GH levels, and GH area under the curves (AUCs) were significantly lower after GHRH + cortisone as compared to GHRH alone. However, these parameters were not significantly different after PD + GHRH + cortisone when compared to PD + GHRH and after PD + cortisone when compared to PD alone. We conclude that acute administration of pharmacological amounts of glucocorticoids cannot inhibit the GH response to PD alone or in combination with GHRH. Thus, we hypothesize that the inhibitory action of glucocorticoids on the GH response to GHRH in man may be mediated by an enhancement of either somatostatin release by the hypothalamus or somatostatin action on the pituitary.
- Published
- 1990
- Full Text
- View/download PDF
16. Effects of calcitonin on GH response to pyridostigmine in combination with hGHRH (1-29) NH2 in normal adult subjects.
- Author
-
Giustina A, Bodini C, Bossoni S, Doga M, Girelli A, Pizzocolo G, and Wehrenberg WB
- Subjects
- Adult, Depression, Chemical, Female, Growth Hormone blood, Growth Hormone-Releasing Hormone pharmacology, Humans, Hydrocortisone blood, Kinetics, Male, Pituitary Gland metabolism, Sermorelin, Calcitonin pharmacology, Growth Hormone metabolism, Growth Hormone-Releasing Hormone analogs & derivatives, Peptide Fragments pharmacology, Pituitary Gland drug effects, Pyridostigmine Bromide pharmacology
- Abstract
Studies in man demonstrated that salmon calcitonin (sCT) administration blunts the pituitary GH response to GH-releasing hormone (GHRH). However, the mechanisms underlying this inhibitory action of CT in man are unclear. Pyridostigmine (PD), an acetylcholinesterase inhibitor, is hypothesized to enhance the GH response to GHRH in normal subjects probably via a decrease in the somatostatinergic tone. The aim of the present study was to investigate the mechanism of the inhibitory action of sCT on the GH response to human GHRH (1-29) NH2 by concomitant PD administration in normal humans. The GH response to GHRH was significantly suppressed by prior administration of sCT. Pretreatment of subjects with PD significantly enhanced the GH response to GHRH but did not alter the inhibitory actions of sCT. We conclude that sCT is able to inhibit GHRH-stimulated GH secretion in man without influencing the hypothalamic somatostatinergic tone.
- Published
- 1990
- Full Text
- View/download PDF
17. Central alpha-2 adrenergic function in patients with essential hypertension. Comparative study of growth hormone (GH) secretion stimulated by clonidine and GH-releasing hormone.
- Author
-
Giustina A, Doga M, Bossoni S, Bodini C, Legati F, Pizzocolo G, and Romanelli G
- Subjects
- Adult, Blood Glucose metabolism, Blood Pressure drug effects, Female, Humans, Kinetics, Male, Receptors, Adrenergic, alpha drug effects, Clonidine pharmacology, Growth Hormone metabolism, Growth Hormone-Releasing Hormone pharmacology, Hypertension physiopathology, Receptors, Adrenergic, alpha physiology
- Published
- 1990
- Full Text
- View/download PDF
18. Acute effects of cortisone acetate on growth hormone response to growth hormone-releasing hormone in normal adult subjects.
- Author
-
Giustina A, Doga M, Bodini C, Girelli A, Legati F, Bossoni S, and Romanelli G
- Subjects
- Adult, Cortisone administration & dosage, Cortisone pharmacology, Dose-Response Relationship, Drug, Drug Synergism, Female, Growth Hormone metabolism, Humans, Male, Cortisone analogs & derivatives, Growth Hormone blood, Growth Hormone-Releasing Hormone administration & dosage, Hydrocortisone blood
- Abstract
Glucocorticoids have been shown to inhibit GH secretion in normal man when administered in large amounts for several days. The aim of our study was 1. to investigate the acute effects of a single dose of glucocorticoids on GH secretion in normal man; 2. to look at the relationship between the increase in serum cortisol concentration and GH response to the stimuli. Six healthy volunteers received on three occasions in random order an iv injection of GHRH (1-29) NH2, 100 micrograms, alone or 60 min after oral administration of either 25 or 50 mg of cortisone acetate. Mean stimulated GH levels, GH peak and integrated GH concentration were significantly lower after GHRH plus cortisone 25 mg than after GHRH alone. Mean GH levels at 15 and 30 min after GHRH injection and the peak GH level showed a further decrease after GHRH plus cortisone 50 mg. We conclude that acute administration of pharmacological doses of glucocorticoids is able to inhibit GH response to GHRH, probably through enhancement of endogenous somatostatin release. Moreover, this pharmacological effect of glucocorticoids seems to be dose-dependent and thus directly related to serum cortisol concentrations.
- Published
- 1990
- Full Text
- View/download PDF
19. Effects of short-term glucocorticoid deprivation on growth hormone (GH) response to GH-releasing hormone in man.
- Author
-
Giustina A, Romanelli G, Bossoni S, Girelli A, Pizzocolo G, Valentini U, and Zuccato F
- Subjects
- Adult, Cortisone administration & dosage, Cortisone therapeutic use, Female, Humans, Time Factors, Adrenocorticotropic Hormone deficiency, Cortisone analogs & derivatives, Growth Hormone metabolism, Growth Hormone-Releasing Hormone, Substance Withdrawal Syndrome blood
- Published
- 1989
- Full Text
- View/download PDF
20. Bone ultrasonometric features and grow hormone secretion in asthmatic patients during chronic inhaled corticosteroid therapy
- Author
-
Malerba, M., Bossoni, S., Radaeli, A., Mori, E., Romanelli, Giuseppe, Tantucci, Claudio, Giustina, Andrea, Grassi, V., Malerba, M., Bossoni, S., Radaeli, A., Mori, E., Romanelli, G., Tantucci, C., Giustina, Andrea, and Grassi, V.
- Subjects
Quantitative bone ultrasound densitometry ,Asthma inhaled corticosteroids ,Growth hormone ,Asthma inhaled corticosteroid - Abstract
Background: Quantitative ultrasound bone densitometry (QUBD) is a new method to assess bone mineral density and bonemicroarchitecture. Corticosteroid (CS) therapy may diminish bone mass, alter bone quality and may influence growth hormone (GH)secretion and bone metabolism markers. Therefore, the aim of this study was to evaluate the effects of long-term therapy with inhaled CSs(ICSs) on structural bone characteristics and their correlations with GH secretion and bone markers in asthmatic patients.Methods: In a cross-sectional study, we enrolled 60 adult patients with mild to moderate persistent asthma: 22 on chronic (N1 year) ICStherapy, 10 naive to ICSs treatment and 28 healthy control subjects. The groups were matched for age and BMI. Each subject underwent toQUBD at the phalanxes to assess bone microarchitecture by ultrasound bone profile index (UBPI), bone density by amplitude-dependentspeed of sound (AdSos); test with GH-releasing hormone (GHRH) injection with calculation of peak GH and the Δ GH (peak GH–basalGH); and hormonal and bone markers measurements.Results: Asthmatics treated with long-term ICS therapy showed a lower UBPI (P b 0.01) compared to controls (49.8 ± 19.3 vs. 77.0 ± 10.1,respectively) and to asthmatics never taking ICSs (73.2 ± 9.6). In ICS-treated asthmatics, ΔGH and GH-peak showed a significant correlationwith UBPI. A significant difference was observed comparing asthmatics treated with ICSs to controls and asthmatics naive to ICSs in GHresponse to GHRH iv bolus. Serum osteocalcin was significantly reduced in asthmatic patients treated with ICSs.Conclusions: In asthmatic patients, long-term ICSs treatment produces negative effects on bone quality assessed by QUBD, and such effectsare associated to an impaired GH secretion.
- Published
- 2006
21. Effect of acute and sustained GH inhibition with octreotide on heart rate variability in active acromegaly
- Author
-
Perini, P., Macadri, C., Doga, M., Cappelli, Carlo, Bossoni, S., Volterrani, M., Giustina, Andrea, Perini, P., Macadri, C., Doga, M., Cappelli, C., Bossoni, S., Volterrani, M., and Giustina, Andrea
- Subjects
growth hormone ,Acromegaly - Published
- 1998
22. Central alpha-2 adrenergic function in patients with essential hypertension. Comparative study of growth hormone (GH) secretion stimulated by clonidine and GH-releasing hormone
- Author
-
GIUSTINA , ANDREA, Doga M, Bossoni S, Bodini C, Legati F, Pizzocolo G, Romanelli G., Giustina, Andrea, Doga, M, Bossoni, S, Bodini, C, Legati, F, Pizzocolo, G, and Romanelli, G.
- Subjects
Adult ,Blood Glucose ,Male ,Kinetics ,Growth Hormone ,Hypertension ,Humans ,Blood Pressure ,Female ,Receptors, Adrenergic, alpha ,Growth Hormone-Releasing Hormone ,Clonidine - Published
- 1990
23. Growth hormone in glucocorticoid-induced osteoporosis
- Author
-
F, Manelli, R, Carpinteri, S, Bossoni, A, Burattin, S, Bonadonna, E, Agabiti Rosei, A, Giustina, Manelli, F, Carpinteri, R, Bossoni, S, Burattin, A, Bonadonna, S, Agabiti Rosei, E, and Giustina, Andrea
- Subjects
Growth Hormone ,Animals ,Humans ,Osteoporosis ,Glucocorticoids ,Bone and Bones - Published
- 2002
24. Reciprocal relationship between the level of circulating cortisol and growth hormone secretion in response to growth hormone-releasing hormone in man: studies in patients with adrenal insufficiency
- Author
-
William B. Wehrenberg, Johannes D. Veldhuis, Laura Chiesa, Enrico Bresciani, Andrea Giustina, Simonetta Bossoni, Valentina Misitano, Giustina, Andrea, Bresciani, E, Bossoni, S, Chiesa, L, Misitano, V, Wehrenberg, Wb, and Veldhuis, Jd
- Subjects
Adult ,Male ,endocrine system ,medicine.medical_specialty ,Hydrocortisone ,medicine.drug_class ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Clinical Biochemistry ,Adrenal Gland Diseases ,Peptide hormone ,Biology ,Growth Hormone-Releasing Hormone ,Biochemistry ,Body Mass Index ,Endocrinology ,Bolus (medicine) ,Addison Disease ,Internal medicine ,medicine ,Humans ,Saline ,Aged ,Sermorelin ,Biochemistry (medical) ,Middle Aged ,Growth hormone–releasing hormone ,Growth hormone secretion ,Growth Hormone ,Injections, Intravenous ,Corticosteroid ,Female ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug - Abstract
The aim of our study was to elucidate the relationship between the level of circulating cortisol and the GH responsiveness to GHRH in six hypoadrenal patients (one male and five females; age range, 35-67 yr; body mass index range, 18-31 kg/m2). Twenty-four hours after taking the last dose of replacement therapy, each patient underwent the following experimental trials on nonconsecutive days: 1) saline, and 2) 12.5 mg, or 3) 25 mg, or 4) 250 mg hydrocortisone hemisuccinate in 250 mL saline constant iv infusion from 0-180 min. On each occasion, 1 micrograms/kg human GHRH-(1-29)NH2 was injected as an iv bolus at 60 min. During GHRH and saline infusion, serum cortisol levels were always less than the detection limit of the assay (55 nmol/L). During 12.5-, 25-, and 250-mg hydrocortisone infusions (from 15-180 min), serum cortisol averaged 413.8 +/- 19.3, 772.5 +/- 46.9, and 1520.2 +/- 110.4 nmol/L, respectively. The GH peaks after GHRH treatment during the various infusions of hydrocortisone were compared to the GH peaks observed after saline, which were normalized to 100% in each subject. GH peaks after GHRH and 25 mg hydrocortisone (70 +/- 11%) and GHRH and 250 mg hydrocortisone (69 +/- 7%) were significantly (P < 0.05) lower than the GH peaks after GHRH and saline or GHRH and 12.5 mg hydrocortisone (83 +/- 15%). No significant differences were observed between the GH peaks after GHRH and 12.5 mg hydrocortisone or GHRH and saline. Our data demonstrate that in hypoadrenal patients, the acute absence of circulating cortisol does not impair the GH secretory response to GHRH with respect to the eucortisolemic state. Moreover, our data suggest that 700 nmol/L is the approximate threshold serum cortisol concentration above which a decrease in the GH responsiveness to GHRH is observed in humans. Further increases in serum cortisol levels above this threshold value do not cause a proportional decrease in the GH responsiveness to GHRH.
- Published
- 1994
25. Effects of metoclopramide on the paradoxical growth hormone response to galanin in acromegaly
- Author
-
Mauro Doga, Corrado Bodini, Andrea Giustina, Simonetta Bossoni, Anna Rosa Bussi, Enrico Bresciani, Giustina, Andrea, Doga, M, Bodini, C, Bossoni, S, Bresciani, E, and Bussi, Ar
- Subjects
Adult ,Male ,medicine.medical_specialty ,Time Factors ,Metoclopramide ,medicine.medical_treatment ,Radioimmunoassay ,Neuropeptide ,Galanin ,Body Mass Index ,Endocrinology ,Internal medicine ,Acromegaly ,Medicine ,Humans ,Infusions, Intravenous ,Saline ,Aged ,business.industry ,Dopaminergic ,General Medicine ,Middle Aged ,medicine.disease ,Growth hormone secretion ,Growth Hormone ,Pituitary Gland ,Female ,business ,Peptides ,medicine.drug ,Hormone - Abstract
Galanin is able to enhance growth hormone (GH)-releasing hormone stimulated GH secretion in normal man. In acromegaly circulating GH levels are elevated and the GH response to GHRH may be exaggerated. Galanin has been recently shown to decrease circulating GH levels in acromegaly. Dopaminergic drugs were the only previously known agents able to cause a paradoxical GH fall in acromegaly. Aim of our study was to investigate the effects of a potent central dopaminergic receptor blocker, metoclopramide (MCP), on the galanin-induced paradoxical GH secretion in acromegalic subjects. Two male and three female patients with active acromegaly (age range 44-66 years, body mass index range 24.6-28 Kg/m2) were studied after 45 min i.v. infusion of porcine galanin (0.5 mg in 100 ml of saline) from 0 to 45 min combined with a 60 min i.v. infusion of a) saline (100 ml) or b) MCP (10 mg in 100 ml of saline) from -15 to 45 min. After galanin, GH values fell from baseline (27.5 +/- 10 micrograms/L) to a mean nadir of 16.4 +/- 6.1 micrograms/L; after galanin + MCP, circulating GH levels were also decreased (mean nadir 17.3 +/- 8.1 micrograms/L) in all the patients with respect to baseline (23.6 +/- 9.7 micrograms/L). No significant differences were found in absolute or percent of baseline GH levels after galanin+saline vs galanin + MCP. Our results suggest that the paradoxical GH fall after galanin in acromegalic patients is not mediated through dopaminergic receptor. It can be hypothesized that galanin may interact at the pituitary level with its own receptors expressed by GH-secreting adenomatous cells.
- Published
- 1993
26. Effect of galanin on the growth hormone (GH) response to GH-releasing hormone in patients with Cushing's disease
- Author
-
William B. Wehrenberg, Andrea Giustina, Anna Rosa Bussi, Simonetta Bossoni, Alessandro Pozzi, Giustina, Andrea, Bossoni, S, Bussi, Ar, Pozzi, A, and Wehrenberg, Wb
- Subjects
Adenoma ,Adult ,endocrine system ,medicine.medical_specialty ,Time Factors ,medicine.medical_treatment ,Galanin ,Growth Hormone-Releasing Hormone ,Cushing syndrome ,Endocrinology ,Bolus (medicine) ,Internal medicine ,medicine ,Humans ,Pituitary Neoplasms ,Single-Blind Method ,Saline ,Cushing Syndrome ,Analysis of Variance ,business.industry ,Neuropeptides ,General Medicine ,Cushing's disease ,Middle Aged ,medicine.disease ,Growth hormone secretion ,Pathophysiology ,Growth Hormone ,Female ,business ,Peptides ,hormones, hormone substitutes, and hormone antagonists ,Hormone - Abstract
Attenuated plasma GH secretion during sleep and blunted GH responses to provocative stimuli have been observed in patients with Cushing's disease. Synthetic porcine galanin elicits GH secretion when given alone, and enhances the GH response to GHRH in normal human subjects. The aim of our study was to investigate the effects of galanin on the GH response to GHRH in patients with Cushing's disease. We studied 5 female subjects with untreated active Cushing's disease caused by micro-pituitary adenomas (age 43 +/- 6.7 years; BMI 30 +/- 0.7 kg/m2). Four normal adult females, matched for age and body weight with the patients with Cushing's disease, were studied as controls. Subjects underwent in random order: (1) infusion of synthetic porcine galanin IV, 500 micrograms in 100 mL; (2) infusion of saline, IV, 100 mL. A bolus of human GHRH(1-29)NH2 (Geref, Serono, Italy), 100 micrograms in 1 mL saline, was injected IV at 0 minutes. Patients with Cushing's disease showed blunted GH peaks after GHRH (1.2 +/- 0.4 micrograms/L) during saline infusion, as compared to normal controls (24.6 +/- 4.6 micrograms/L; p0.05). During galanin infusion a significantly enhanced GH response to GHRH, as compared with saline infusion, was observed in control subjects (GH peak: 51.4 +/- 9.8 micrograms/L; p0.05), but not in patients with Cushing's disease (GH peak: 2.3 +/- 0.6 micrograms/L). GH levels were significantly lower both after saline and after galanin in patients with Cushing's disease as compared to normal controls. Our data demonstrate that galanin is not able to enhance the GH response to GHRH in patients with Cushing's disease. That galanin cannot reverse this effect suggests that the mechanism of action of galanin is not via a decrease in somatostatin release by the hypothalamus.
- Published
- 1993
27. Arginine blocks the inhibitory effect of hydrocortisone on circulating growth hormone levels in patients with acromegaly
- Author
-
Anna Rosa Bussi, Massimo Licini, Andrea Giustina, M. Schettino, S Bossoni, M. Doga, William B. Wehrenberg, Giustina, Andrea, Schettino, M, Bossoni, S, Bussi, Ar, Doga, M, Licini, M, and Wehrenberg, Wb
- Subjects
Adult ,Male ,medicine.medical_specialty ,Time Factors ,Hydrocortisone ,Arginine ,Somatostatin secretion ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Endocrinology ,Bolus (medicine) ,Internal medicine ,Acromegaly ,Humans ,Medicine ,Infusions, Intravenous ,Saline ,Chemotherapy ,business.industry ,Middle Aged ,medicine.disease ,Drug Combinations ,Growth Hormone ,Female ,business ,medicine.drug ,Hormone - Abstract
In patients with acromegaly, circulating growht hormone (GH) levels and GH responses to GH-releasing hormone (GHRH) are decreased by long-term administration of pharmacological doses of glucocorticoids. The aim of our study was to investigate the acute effects of intravenous (IV) infusion of hydrocortisone combined either with saline or arginine infusion on circulating GH levels in acromegaly. We studied five adult patients with acromegaly, two men and three women aged 54.6 ± 4 years having a body mass index of 25.9 ± 1.2 kg/m 2 . On two randomized occasions, patients underwent a bolus IV injection of 100 mg hydrocortisone succinate at time 0 followed by a 120-minute IV infusion of 250 mg hydrocortisone in 250 mL saline, combined with a 90-minute (from −15 to 75 minutes) IV infusion of (1) 60 g arginine hydrochloride in 200 mL saline, or (2) 200 mL saline. In all of the acromegalic patients during the infusion of hydrocortisone alone, serum GH levels clearly decreased (nadir range, 26.4% to 68.1%) with respect to GH levels before hydrocortisone administration (mean of time −15 and 0, basal level), with a nadir between 90 and 180 minutes after the beginning of the infusion. After arginine pretreatment, GH levels were significantly enhanced compared with levels attained with hydrocortisone saline, and they were also significantly increased (peak, 167.5% ± 27.7%) with respect to basal levels. Our data show that arginine blocks the inhibitory effect of acute and sustained hypercortisolism on circulating GH levels in acromegaly. It also seems likely that in both acromegalic patients and normal subjects, acute increases in serum cortisol levels may cause an enhancement of hypothalamic somatostatin secretion, which in turn may be responsible for the glucocorticoid-mediated GH inhibition.
- Published
- 1993
28. Variability in the growth hormone response to growth hormone-releasing hormone alone or combined with pyridostigmine in type 1 diabetic patients
- Author
-
Corrado Bodini, Umberto Valentini, W. B. Wehrenberg, Andrea Giustina, Simonetta Bossoni, Giustina, Andrea, Bodini, C, Bossoni, S, Valentini, U, and Wehrenberg, Wb
- Subjects
Adult ,Blood Glucose ,Male ,endocrine system ,medicine.medical_specialty ,medicine.drug_class ,Endocrinology, Diabetes and Metabolism ,Population ,Individuality ,Peptide hormone ,Biology ,Placebo ,Endocrinology ,Internal medicine ,medicine ,Humans ,Single-Blind Method ,education ,Type 1 diabetes ,education.field_of_study ,medicine.disease ,Growth hormone–releasing hormone ,Diabetes Mellitus, Type 1 ,Somatostatin ,Pyridostigmine ,Acetylcholinesterase inhibitor ,Growth Hormone ,Female ,hormones, hormone substitutes, and hormone antagonists ,Pyridostigmine Bromide ,medicine.drug - Abstract
In man the GH response to GHRH is variable within and between subjects. Pyridostigmine (PD), an acetylcholinesterase inhibitor, has been shown to reduce the variability of the GH response to GHRH in normal subjects. The aim of this study was to assess the existence of either inter- or intraindividual variability in the GH response to GHRH in type 1 diabetic patients. Moreover, we investigated the effect of PD on such variability in the same patients. Seven (4 females-3 males) nonobese type 1 diabetic patients underwent two experiments performed in consecutive days according to a single-blind protocol: 1) 120 mg oral PD 60 min before iv injection of human (h) GHRH-(1-29) NH2, 100 μg in 2 ml of sterile water; 2) oral placebo 60 min before iv injection of 100 μg hGHRH. The two experiments were then repeated, following the same procedure, one and two weeks after the start of the study. The GH peaks after GHRH were variable within different subjects but also in the same subject on different occasions. However, the mean GH peak levels after GHRH in the three tests were not significantly different (14.2±3.5, 15.3±3, 16.5±6.4 μg/L, respectively), the coefficient of variation for each test was 65%, 51.8%, 102.4%, respectively (mean 73.1±15.1%). The GH response to GHRH was always significantly enhanced by PD administration: the mean GH peak levels in the three tests were 31.9±7.1, 44.8±10.4, 49.9±13.1 μg/L, respectively, without significant differences between tests. After PD+GHRH the interindividual variability in the GH response was still present but significantly lower than after GHRH alone. The coefficient of variation for each test was 58.7%, 61.3%, 69.3%, respectively (mean 63.1±3.2%). It can be hypothesized that PD may reduce the interindividual variability of the GH response to GHRH in the diabetic population by decreasing somatostatin tone only in diabetic patients with normal-high hypothalamic somatostatin.
- Published
- 1993
29. Arginine normalizes the growth hormone (GH) response to GH-releasing hormone in adult patients receiving chronic daily immunosuppressive glucocorticoid therapy
- Author
-
Andrea Giustina, Simonetta Bossoni, Corrado Bodini, Giuseppe Pizzocolo, W B Wehrenberg, Angela Girelli, G P Balestrieri, Giustina, Andrea, Bossoni, S, Bodini, C, Girelli, A, Balestrieri, Gp, Pizzocolo, G, and Wehrenberg, Wb
- Subjects
Adult ,Male ,endocrine system ,medicine.medical_specialty ,Time Factors ,Arginine ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Radioimmunoassay ,Growth Hormone-Releasing Hormone ,Biochemistry ,Endocrinology ,Reference Values ,Internal medicine ,medicine ,Humans ,Immunosuppression Therapy ,business.industry ,Biochemistry (medical) ,Growth hormone–releasing hormone ,Growth hormone secretion ,Somatropin ,Kinetics ,Somatostatin ,Growth Hormone ,Prednisone ,Secretagogue ,Female ,business ,hormones, hormone substitutes, and hormone antagonists ,Glucocorticoid ,medicine.drug ,Hormone - Abstract
Glucocorticoids are thought to inhibit GH secretion through an enhancement of endogenous somatostatin tone. The aim of our study was to evaluate the effect of arginine, a secretagogue that increases GH secretion acting at the hypothalamic level, probably by decreasing somatostatin tone, on GH-releasing hormone (GHRH)-induced GH secretion in three male and five female adult patients with nonendocrine disease who were receiving daily immunosuppressive glucocorticoid therapy. Six normal subjects (four males and two females) served as controls. GHRH-induced GH secretion was evaluated after 30-min iv infusion of saline (100 mL) or arginine (30 g) in 100 mL saline. After saline administration, steroid-treated patients showed a blunted GH response to GHRH (GH peak, 8.7 +/- 2.4 micrograms/L) compared to that of normal subjects (GH peak, 23.8 +/- 3.9 micrograms/L). The GH responses to GHRH increased (P less than 0.05) after pretreatment with arginine compared to saline pretreatment in both normal subjects (GH peak, 36.6 +/- 4.0 micrograms/L) and steroid-treated patients (GH peak, 28.4 +/- 5.5 micrograms/L). The GH responses to GHRH plus arginine were not significantly different in steroid-treated and normal subjects. Thus, arginine is able to normalize the GH response to GHRH in patients receiving chronic glucocorticoid treatment. Our data are evidence that the stimulatory action of arginine and the inhibitory action of glucocorticoids on GH secretion are mediated by opposite effects on hypothalamic somatostatin tone.
- Published
- 1992
30. The role of cholinergic tone in modulating the growth hormone response to growth hormone-releasing hormone in normal man
- Author
-
William B. Wehrenberg, Angela Girelli, Andrea Giustina, S Bossoni, Corrado Bodini, Maria Grazia Buffoli, M. Schettino, M. Doga, Giustina, Andrea, Bossoni, S, Bodini, C, Doga, M, Girelli, A, Buffoli, Mg, Schettino, M, and Wehrenberg, Wb
- Subjects
Adult ,Male ,endocrine system ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Microgram ,Placebo ,Growth Hormone-Releasing Hormone ,Placebos ,Endocrinology ,Bolus (medicine) ,Parasympathetic Nervous System ,Reference Values ,Internal medicine ,medicine ,Humans ,Dose-Response Relationship, Drug ,business.industry ,Growth hormone–releasing hormone ,Growth hormone secretion ,Dose–response relationship ,Somatostatin ,Pyridostigmine ,Growth Hormone ,Female ,business ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug ,Pyridostigmine Bromide - Abstract
Growth hormone-releasing hormone (GHRH) increases serum GH levels in a dose-dependent manner. Pyridostigmine (PD), an acetylcholinesterase inhibitor, is able to elicit GH secretion when administered alone and to enhance the GH response to GHRH in normal subjects, probably via a decrease in the hypothalamic release of somatostatin. The aim of the present study was to investigate if an enhancement of the cholinergic tone was able to influence the dose-response relationship between GHRH and GH in normal adult subjects. Six healthy adult volunteers underwent 10 experimental protocols. They were: human GHRH (1-29)NH2, 1 micrograms/kg injected as an intravenous (IV) bolus 60 minutes after (a) PD, 120 mg administered orally, or (b) placebo, two tablets administered orally; GHRH, 0.3 micrograms/kg injected as an IV bolus 60 minutes after (c) PD or (d) placebo; GHRH, 0.1 micrograms/kg injected as an IV bolus 60 minutes after (e) PD or (f) placebo; GHRH, 0.01 micrograms/kg injected as an IV bolus 60 minutes after (g) PD or (h) placebo; saline, 1 mL injected as an IV bolus 60 minutes after (i) PD or (l) placebo. The GH response in placebo-treated subjects was similar after 1 microgram/kg and 0.3 microgram/kg GHRH, while the 0.1 microgram/kg dose elicited a lower response. The 0.01 microgram/kg dose of GHRH did not significantly increase GH levels as compared with saline. After PD, the GH responses to GHRH were greatly enhanced at all doses tested: 1.0, 0.3, and 0.1 microgram/kg GHRH all elicited similar GH responses; the GH response to 0.01 microgram/kg GHRH was lower, but was still higher than that observed after saline.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1991
31. Pyridostigmine enhances even if it does not normalize the growth hormone responses to growth hormone-releasing hormone in patients with Cushing's disease
- Author
-
Giuseppe Pizzocolo, Corrado Bodini, Tiziano Scalvini, Andrea Giustina, Maurizio Schettino, Simonetta Bossoni, William B. Wehrenberg, Carlo Ferrari, Giustina, Andrea, Bossoni, S, Bodini, C, Ferrari, C, Pizzocolo, G, Scalvini, T, Schettino, M, and Wehrenberg, Wb
- Subjects
Adenoma ,Adult ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Radioimmunoassay ,Administration, Oral ,Placebo ,Growth Hormone-Releasing Hormone ,Cushing syndrome ,Endocrinology ,Internal medicine ,medicine ,Humans ,Pituitary Neoplasms ,Cushing Syndrome ,business.industry ,Antibodies, Monoclonal ,Cushing's disease ,Growth hormone–releasing hormone ,medicine.disease ,Growth hormone secretion ,Somatostatin ,Pyridostigmine ,Growth Hormone ,Injections, Intravenous ,Female ,business ,medicine.drug ,Hormone ,Pyridostigmine Bromide - Abstract
Subjects with Cushing's disease have diminished growth hormone (GH) response to growth hormone-releasing hormone (GHRH). The aim of our study was to investigate the underlying mechanism of this diminished GH response in these patients using pyridostigmine (PD), an acetylcholinesterase inhibitor, which is reported to increase GH secretion by reducing somatostatin tone. Eight subjects with untreated Cushing's disease (caused by a pituitary adenoma) and 6 control subjects received GHRH 100 micrograms in 1 ml of saline, as intravenous bolus injection 60 min after (1) placebo (2 tablets, p.o.) or (2) PD (120 mg, p.o.). After GHRH plus placebo, the GH peak (mean +/- SEM) was significantly lower in subjects with Cushing's disease (2.4 +/- 0.5 micrograms/l) compared to control subjects (25.1 +/- 1.8 micrograms/l, p less than 0.05). After GHRH plus PD, the GH peak was significantly enhanced both in subjects with Cushing's disease (7.1 +/- 2.3 micrograms/l, p less than 0.05) and in control subjects (42.3 +/- 4.3 micrograms/l, p less than 0.05). In patients with Cushing's disease, the GH response to GHRH plus PD was lower with respect to the GH response to GHRH alone in normal subjects. We conclude that hypercortisolism may cause a decrease in central cholinergic tone which is in turn hypothesized to be responsible of an enhanced somatostatin release from the hypothalamus. However, other metabolic or central nervous system alterations may act synergistically with hypercortisolism in causing GH inhibition in patients with Cushing's disease.
- Published
- 1991
32. Effects of pyridostigmine on spontaneous and growth hormone-releasing hormone stimulated growth hormone secretion in children on daily glucocorticoid therapy after liver transplantation
- Author
-
William B. Wehrenberg, Andrea Giustina, Maurlzlo Schettino, Mauro Doga, Simonetta Bossonl, Angela Girelli, Danlele Albert, Fabio Buzl, Giustina, Andrea, Girelli, A, Alberti, D, Bossoni, S, Buzi, F, Doga, M, Schettino, M, and Wehrenberg, Wb
- Subjects
Male ,medicine.medical_specialty ,Prednisolone ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Hypothalamus ,Liver transplantation ,Growth Hormone-Releasing Hormone ,Placebo ,Endocrinology ,Internal medicine ,medicine ,Humans ,Single-Blind Method ,Child ,business.industry ,Growth hormone–releasing hormone ,Growth hormone secretion ,Liver Transplantation ,Somatostatin ,Pyridostigmine ,Child, Preschool ,Growth Hormone ,Cyclosporine ,Female ,business ,Glucocorticoid ,Pyridostigmine Bromide ,medicine.drug ,Hormone - Abstract
OBJECTIVES: We aimed to investigate both nocturnal spontaneous and morning growth hormone (GH)-releasing hormone (GHRH)-induced GH secretion in children on daily glucocorticoid treatment after liver transplantation and to evaluate the effect of pyridostigmine (an acetylcholinesterase inhibitor thought to reduce hypothalamic somatostatin tone) on GH secretion in these patients. DESIGN: We performed a randomized, single-blind, cross-over study. PATIENTS: We studied three male and three female juvenile patients, within a year of orthotopic liver transplantation and under immunosuppressive glucocorticoid therapy (mean dose +/- SEM, 5.92 +/- 0.63 mg/day) and five normal children (four males, one female). MEASUREMENTS: Both nocturnal spontaneous and morning GHRH-induced GH secretion were evaluated after administration of placebo, 1 tablet p.o., or pyridostigmine, 2 mg/kg p.o. RESULTS: Spontaneous GH. Placebo: in liver transplanted children nocturnal GH secretion (mean GH level 10.8 +/- 2.0 mU/l) was not significantly different with respect to normal children (mean GH level 12.8 +/- 1.2 mU/l); pyridostigmine: nocturnal GH secretion was significantly increased as compared to placebo in subjects with liver transplantation but not in normal children. GHRH test. Placebo: liver transplanted patients showed a blunted GH response to GHRH with respect to normal children; pyridostigmine: the GH responses to GHRH (P less than 0.05) increased as compared to placebo and did not differ significantly in the two groups. CONCLUSIONS: Our data suggest a steroid-mediated increase in hypothalamic somatostatin tone in liver transplanted children
- Published
- 1991
33. Impaired growth hormone (GH) response to pyridostigmine in type 1 diabetic patients with exaggerated GH-releasing hormone-stimulated GH secretion
- Author
-
Giuseppe Romanelli, Giuseppe Pizzocolo, Andrea Giustina, Simonetta Bossoni, Antonino Cimino, William B. Wehrenberg, Giustina, Andrea, Bossoni, S, Cimino, A, Pizzocolo, G, Romanelli, G, and Wehrenberg, Wb
- Subjects
Adult ,Male ,endocrine system ,medicine.medical_specialty ,Adolescent ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Peptide hormone ,Biology ,Biochemistry ,Gonadotropin-Releasing Hormone ,Basal (phylogenetics) ,Endocrinology ,Internal medicine ,Diabetes mellitus ,medicine ,Humans ,Glycated Hemoglobin ,Biochemistry (medical) ,Drug Synergism ,medicine.disease ,Growth hormone secretion ,Kinetics ,Somatostatin ,Diabetes Mellitus, Type 1 ,Pyridostigmine ,Hypothalamus ,Growth Hormone ,Female ,Cholinesterase Inhibitors ,hormones, hormone substitutes, and hormone antagonists ,Hormone ,medicine.drug ,Pyridostigmine Bromide - Abstract
In the present study we investigated the effects of the acetylcholinesterase inhibitor pyridostigmine (PD), which is hypothesized to decrease hypothalamic somatostatin tone, alone and in association with GH-releasing hormone (GHRH) on GH secretion in 18 type 1 diabetic patients and 12 normal subjects using a randomized double blind placebo-controlled protocol. All subjects received either 120 mg oral PD or placebo 60 min before iv injection of either human GHRH-(1-29) NH2 (100 micrograms) or sterile water (2 mL). In normal subjects both PD alone and GHRH alone caused a significant increase in GH. PD and GHRH acted in a synergistic fashion when combined. In diabetic patients the GH response to GHRH was variable. To segregate the responses, the ratio between the GH increase after GHRH plus PD and after GHRH alone was calculated for each subject. In 10 diabetic patients (group A) the ratio was lower than 2 SD (P less than 0.05) from the mean response of normal subjects. These patients showed an exaggerated GH increase after GHRH and a lower GH increase after PD with respect to normal subjects. Eight diabetic patients (group B) showed a ratio similar to that in normal subjects and similar GH responses to the stimuli. No significant differences were found between groups A and B with respect to age, body mass index, and blood glucose levels. Duration of diabetes was longer and basal GH levels were higher in group A. Hemoglobin-A1c was higher in group A, but of only borderline statistical significance (P = 0.052). Our data demonstrate that in diabetic patients with exaggerated GH responses to GHRH an increase in cholinergic tone does not affect GH secretion. These data suggest that in some type 1 diabetic patients an altered somatostatinergic control of GH secretion may contribute to their abnormal GH response to GHRH.
- Published
- 1990
34. Acute effects of cortisone acetate on growth hormone response to growth hormone-releasing hormone in normal adult subjects
- Author
-
Mauro Doga, Corrado Bodini, Giuseppe Romanelli, Andrea Giustina, Simonetta Bossoni, Fabio Legati, Angela Girelli, Giustina, Andrea, Doga, M, Bodini, C, Girelli, A, Legati, F, Bossoni, S, and Romanelli, G.
- Subjects
Adult ,Male ,endocrine system ,medicine.medical_specialty ,Somatotropic cell ,Hydrocortisone ,Endocrinology, Diabetes and Metabolism ,Gonadotropic cell ,Growth Hormone-Releasing Hormone ,Endocrinology ,Oral administration ,Internal medicine ,Medicine ,Humans ,Dose-Response Relationship, Drug ,business.industry ,Drug Synergism ,General Medicine ,Growth hormone–releasing hormone ,Growth hormone secretion ,Cortisone ,Somatostatin ,Growth Hormone ,Female ,business ,hormones, hormone substitutes, and hormone antagonists ,Endocrine gland ,medicine.drug - Abstract
Glucocorticoids have been shown to inhibit GH secretion in normal man when administered in large amounts for several days. The aim of our study was 1. to investigate the acute effects of a single dose of glucocorticoids on GH secretion in normal man; 2. to look at the relationship between the increase in serum cortisol concentration and GH response to the stimuli. Six healthy volunteers received on three occasions in random order an iv injection of GHRH (1–29) NH2, 100 μg, alone or 60 min after oral administration of either 25 or 50 mg of cortisone acetate. Mean stimulated GH levels, GH peak and integrated GH concentration were significantly lower after GHRH plus cortisone 25 mg than after GHRH alone. Mean GH levels at 15 and 30 min after GHRH injection and the peak GH level showed a further decrease after GHRH plus cortisone 50 mg. We conclude that acute administration of pharmacological doses of glucocorticoids is able to inhibit GH response to GHRH, probably through enhancement of endogenous somatostatin release. Moreover, this pharmacological effect of glucocorticoids seems to be dose-dependent and thus directly related to serum cortisol concentrations.
- Published
- 1990
35. Pyridostigmine blocks the inhibitory effect of glucocorticoids on growth hormone-releasing hormone stimulated growth hormone secretion in normal man
- Author
-
Giuseppe Romanelli, Andrea Giustina, Simonetta Bossoni, Corrado Bodini, William B. Wehrenberg, Mauro Doga, Angela Girelli, Giustina, Andrea, Girelli, A, Doga, M, Bodini, C, Bossoni, S, Romanelli, G, and Wehrenberg, Wb
- Subjects
Adult ,Male ,medicine.medical_specialty ,Hydrocortisone ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Hypothalamus ,Peptide hormone ,Biology ,Growth Hormone-Releasing Hormone ,Biochemistry ,Endocrinology ,Bolus (medicine) ,Internal medicine ,medicine ,Humans ,Glucocorticoids ,Sermorelin ,Biochemistry (medical) ,Growth hormone–releasing hormone ,Growth hormone secretion ,Cortisone ,Somatostatin ,Pyridostigmine ,Growth Hormone ,Pituitary Gland ,Female ,Pyridostigmine Bromide ,medicine.drug - Abstract
Glucocorticoids have been shown to inhibit GH secretion in normal man when acutely and chronically administered in pharmacological amounts. Pyridostigmine (PD), an acetylcholinesterase inhibitor, is able to elicit GH secretion when administered alone and to enhance the GH response to GHRH in normal subjects probably via a decrease in the hypothalamic release of somatostatin. The aim of the present study was to investigate the influence of glucocorticoids on the GH response to PD administered either alone or in combination with GHRH in normal adult subjects. Six healthy adult volunteers underwent six experimental protocols. They received 1) human (h) GHRH(1-29)NH2, 100 micrograms injected as an iv bolus; 2) cortisone acetate, 50 mg administered orally (po) 60 min before an hGHRH iv bolus injection; 3) PD, 120 mg administered po, 60 min before an hGHRH iv bolus injection; 4) PD and cortisone acetate, administered po 60 min before an hGHRH iv bolus injection; 5) PD, administered po 60 min before a saline iv bolus injection; 6) PD and cortisone acetate administered po 60 min before a saline iv bolus injection. Mean GH levels, peak GH levels, and GH area under the curves (AUCs) were significantly lower after GHRH + cortisone as compared to GHRH alone. However, these parameters were not significantly different after PD + GHRH + cortisone when compared to PD + GHRH and after PD + cortisone when compared to PD alone. We conclude that acute administration of pharmacological amounts of glucocorticoids cannot inhibit the GH response to PD alone or in combination with GHRH. Thus, we hypothesize that the inhibitory action of glucocorticoids on the GH response to GHRH in man may be mediated by an enhancement of either somatostatin release by the hypothalamus or somatostatin action on the pituitary.
- Published
- 1990
36. Effects of calcitonin on GH response to pyridostigmine in combination with hGHRH (1-29) NH2 in normal adult subjects
- Author
-
William B. Wehrenberg, Angela Girelli, Corrado Bodini, S Bossoni, M. Doga, Giuseppe Pizzocolo, Andrea Giustina, Giustina, Andrea, Bodini, C, Bossoni, S, Doga, M, Girelli, A, Pizzocolo, G, and Wehrenberg, Wb
- Subjects
Adult ,Calcitonin ,Male ,endocrine system ,medicine.medical_specialty ,Hydrocortisone ,medicine.drug_class ,Endocrinology, Diabetes and Metabolism ,Neuropeptide ,Biology ,Inhibitory postsynaptic potential ,Growth Hormone-Releasing Hormone ,Endocrinology ,hemic and lymphatic diseases ,Internal medicine ,medicine ,Humans ,Sermorelin ,Radioimmunoassay ,Growth hormone secretion ,Peptide Fragments ,Kinetics ,Pyridostigmine ,Acetylcholinesterase inhibitor ,Depression, Chemical ,Growth Hormone ,Pituitary Gland ,Female ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug ,Hormone ,Pyridostigmine Bromide - Abstract
SUMMARY Studies in man demonstrated that salmon calcitonin (sCT) administration blunts the pituitary GH response to GH-releasing hormone (GHRH). However, the mechanisms underlying this inhibitory action of CT in man are unclear. Pyridostigmine (PD), an acetylcholinesterase inhibitor, is hypothesized to enhance the GH response to GHRH in normal subjects probably via a decrease in the somatostatinergic tone. The aim of the present study was to investigate the mechanism of the inhibitory action of sCT on the GH response to human GHRH (1–29) NH2 by concomitant PD administration in normal humans. The GH response to GHRH was significantly suppressed by prior administration of sCT. Pretreatment of subjects with PD significantly enhanced the GH response to GHRH but did not alter the inhibitory actions of sCT. We conclude that sCT is able to inhibit GHRH-stimulated GH secretion in man without influencing the hypothalamic somatostatinergic tone.
- Published
- 1990
37. Effects of short-term glucocorticoid deprivation on growth hormone (GH) response to GH-releasing hormone in man
- Author
-
Giuseppe Pizzocolo, Umberto Valentini, Angela Girelli, Fausto Zuccato, S Bossoni, Giuseppe Romanelli, Andrea Giustina, Giustina, Andrea, Romanelli, G, Bossoni, S, Girelli, A, Pizzocolo, G, Valentini, U, and Zuccato, F.
- Subjects
Adult ,medicine.medical_specialty ,Time Factors ,Endocrinology, Diabetes and Metabolism ,Biochemistry (medical) ,Clinical Biochemistry ,General Medicine ,Peptide hormone ,Biology ,Growth hormone ,Growth Hormone-Releasing Hormone ,Biochemistry ,Substance Withdrawal Syndrome ,Cortisone ,Endocrinology ,Adrenocorticotropic Hormone ,Internal medicine ,Growth Hormone ,medicine ,Humans ,Female ,Glucocorticoid ,medicine.drug ,Hormone - Published
- 1989
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.