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74. Sex differences in the adrenergic response to hypoglycemic stress in human

Author

Mornex R, J. Claustre, Peyrin L, and Fitoussi R

Subjects
Adult, Blood Glucose, Male, medicine.medical_specialty, Sympathetic Nervous System, Time Factors, Urinary system, medicine.medical_treatment, Period (gene), Adrenergic, Stimulus (physiology), Hypoglycemia, Norepinephrine (medication), Catecholamines, Sex Factors, Stress, Physiological, Internal medicine, Humans, Medicine, Pulse, Pharmacology, business.industry, Insulin, medicine.disease, Endocrinology, Epinephrine, Female, business, medicine.drug
Abstract

We have found different patterns of adrenergic response to insulin-induced hypoglycemia in men and women. The differences involve the readiness of adrenergic reactivity, the magnitude of the responses, and the nature of secreted amines. In men, a strong and transient discharge of epinephrine (E) is observed in plasma, corresponding to a great increase in the urinary level of this amine in the 2 h period following insulin. In women, the adrenergic response is delayed and consists of moderately increased amounts of E and norepinephrine (NE) which persist in plasma for a longer period. From the correlations observed between urinary amount and the increase of plasmatic catecholamines after 30, 45, and 60 min, it may be assumed that urinary data may reflect the cumulative plasma levels of catecholamines in the corresponding period, but not the precise pattern of plasmatic changes. Our findings show that the differences in adrenergic behavior previously observed in men and women under the effect of psychological stress, may also be induced by a metabolic stimulus such a insulin hypoglycemia; however, women, but not men, exhibit a mild release of NE under this metabolic stress.

Published
1980
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77. Spectral Analysis of StressInduced Change in Blood Pressure and Heart Rate in Normotensive Subjects

Author

Grillot, M., Fauvel, J. P., Cottet-Emard, J. M., Laville, M., Peyrin, L., Pozet, N., and Zech, P.

Abstract

Changes in spectral analysis of the variability in systolic blood pressure (SBP) and heart rate (HR) were investigated in 12 normotensive volunteers during a well-standardized stress test. BP was measured indirectly from the finger by a noninvasive device (Finapres). The stress test was a computerized version of the Stroop color word conflict test (CWT). The influences of acute (single dose) β1-selective blockade by bisoprolol or angiotensin-converting enzyme (ACE) inhibition by lisinopril were analyzed by a double-blind placebo-controlled trial. During the placebo phase, the efficiency of the stress test was confirmed by a significant increase in SBP (25 ± 11 ). HR (36 ± 23), and plasma concentrations of epinephrine (Epi, 54 ± 37) and norepinephrine (NE. 27 ± 35). Stress induced a significant increase in the amplitude of SBP and HR oscillations in the medium-frequency band (MF. 70− to 140-mHz range), which corresponds to the Mayer waves (27 ± 32 and 42 ± 43, respectively for SBP-MF and HR-MF). The stress-induced increase in NE correlated significantly with the increase in HR (r= 0.68. p < 0.05). The stress-induced increase in SBP-MF correlated significantly with the increase in Epi (r= 0.69. p < 0.05) and in HR-MF (r= 0.69, p < 0.05). A significant decrease in SBP-MF at rest was observed with a single oral (p.o.) dose of bisoprolol, but not of lisinopril. As a noninvasive method, spectral analysis of the variability in SBP and HR may be of benefit in stress-induced modifications of the autonomie nervous system.

Published
1995

80. Catecholamines and fuels after an ultralong run: persistent changes after 24-h recovery

Author

Nicole Fellmann, Peyrin L, Jean Coudert, Jean-Marc Pequignot, M. Sagnol, and J. Claustre

Subjects
Adult, Blood Glucose, Glycerol, Male, medicine.medical_specialty, medicine.medical_treatment, Physical Therapy, Sports Therapy and Rehabilitation, Fatty Acids, Nonesterified, Running, chemistry.chemical_compound, Norepinephrine, Catecholamines, Dopamine, Internal medicine, medicine, Humans, Orthopedics and Sports Medicine, Triglycerides, Triglyceride, Chemistry, Insulin, Lipid metabolism, Carbohydrate, Endocrinology, Epinephrine, Catecholamine, Female, Energy Metabolism, medicine.drug
Abstract

This study examined the alterations induced by an ultralong distance run (169 +/- 6 km in 24 h) and by prolonged postrace recovery (24 h) on blood fuel metabolites and catecholamines in seven trained subjects. Ten minutes after the race, plasma concentrations of glycerol and free fatty acids (FFA) were decreased twofold. Plasma glucose was unchanged. Plasma concentrations of free norepinephrine (NE) and free dopamine (DA) increased from 2.73 +/- 0.28 to 5.41 +/- 1.11 nmol.l-1 and from 0.45 +/- 0.13 to 0.62 +/- 0.18 nmol.l-1 whereas free epinephrine (E) and insulin were unchanged; 24 h after the race, plasma glycerol and FFA concentrations remained elevated (twofold) and TG decreased twofold compared with resting levels. Concomitantly, plasma NE and DA levels remained elevated, respectively, 6.23 +/- 0.41 and 0.77 +/- 0.13 nmol.l-1. These data show that the alterations in circulating fuel metabolites and NE induced by the ultralong race were still present 24 h later. The involvement of lipid metabolism and catecholamines in processes of post-exercise recovery is discussed.

Published
1989

81. Search for a Serotoninergic Mechanism in the Pharmacological Effects of Dopamine on Motricity in the Isolated Rat Duodenum

Author

Peyrin L, Cier Jf, and Miachon S

Subjects
medicine.medical_specialty, Chemistry, Endogeny, Serotonergic, In vitro, Endocrinology, medicine.anatomical_structure, Competitive antagonist, Dopamine, Internal medicine, medicine, Duodenum, Receptor, 5-HT receptor, medicine.drug
Abstract

We observed on the isolated Rat duodenum in vitro an excito- motor effect of dopamine (DA) for concentrations ranging between 10−7 to 10−5M, which was able to be suppressed only after using a serotoninergic blocking agent. To investigate the mechanism of this effect, we studied first the role of the endogenous stores of 5 hydroxytryptamine (5 HT), second the direct effect of DA on serotoninergic receptors. 5 HT tissue stores are not significantly reduced after adding to the duodenum several exciting doses of DA, and the excito- motor effect of DA exists whatever may be the state of the 5 HT endogenous stores (duodenums of animals depleted by treatment with P.C.P.A. or duodenums mechanically deprived of the 5 HT containing cells). The study of the effects of DA on 5 HT receptors show that DA is able to recognize these receptors, having a biphasic effect related to dosis : at concentrations below 10−6M, DA amplifies the pharmacologic effects of 5 HT; at concentrations exceeding on an average 5.10−6 M, DA hinders the effects of 5 HT and behaves as a competitive antagonist against it.

Published
1979
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98. [Biochemical diagnosis of pheochromocytoma and neuroblastomas].

Author

Candito M, Billaud E, Chauffert M, Cottet-Emard JM, Desmoulin D, Garnier JP, Greffe J, Hirth C, Jacob N, Millot F, Nignan A, Patricot MC, Peyrin L, and Plouin PF

Subjects
Adolescent, Catecholamines analysis, Child, Child, Preschool, Homovanillic Acid analysis, Humans, Hydroxylamines analysis, Infant, Quality Control, Vanilmandelic Acid analysis, Neuroblastoma diagnosis, Neuroblastoma metabolism, Pheochromocytoma diagnosis, Pheochromocytoma metabolism
Abstract

Pheochromocytoma and neuroblastoma are distinct tumours, but their biological diagnosis is based on secretion increase of one or several catecholamines. Assays have to be very sensible and specific for an early diagnosis. 24 hours urinary catecholamines and metabolites are currently measured, but technical improvements permit plasma metanephrine assay, an excellent indicator of pheochromocytoma. HPLC coupled to electrochemical detection represents the most efficient methodology. After a review of urinary and plasma assay methods, the authors show usual values of catecholamines, metanephrines, HVA and VMA, according to ages, and give examples of results encountered in classical or not tumours and in falsely positive cases. Urinary metanephrine assay is the most sensible and specific in biological diagnosis of pheochromocytoma, while catecholamines and VMA assays lack of sensibility. Results have to be given by 24 hours and by creatinine ratio. Metanephrine assay can be performed also in plasma and exhibits the same interest. However, in urine as in plasma, in case of renal failure, results cannot be interpreted. Neuroblastoma biological diagnosis is based classically on HVA, VMA, and dopamine assays, nowadays only in 24 hours urine (or in urinary micturition for screening), and results are also expressed as creatinine ratio. But even if several assays are advisable, 5% of the neuroblastoma cases do not produce increased catecholamine values. In some cases, metanephrine assay could be of interest. After the age of 12 months, clinical expression of neuroblastoma is dramatic in 70% of cases. So, a biological screening has been experimented in several countries including France. A French translation of the consensus conference report (1998) is appended, which shows the complexity of neuroblastoma screening. Now, there is no evidence that early tumour detection by screening lessens the mortality rate, but a weak benefit is not excluded.

Published
2002

99. [The diagnosis of atypical pheochromocytoma: a challenge for the biologist as well].

Author

Peyrin L, Cottet-Emard JM, Cottet-Emard RM, and Vouillarmet A

Subjects
Adrenal Gland Neoplasms genetics, Adrenal Gland Neoplasms metabolism, Adult, Aged, Catecholamines analysis, Epinephrine analysis, Epinephrine metabolism, Female, Humans, Hypertension etiology, Male, Metanephrine analysis, Middle Aged, Multiple Endocrine Neoplasia Type 2a genetics, Normetanephrine analysis, Pheochromocytoma genetics, Pheochromocytoma metabolism, Vanilmandelic Acid urine, Adrenal Gland Neoplasms diagnosis, Biomarkers, Tumor analysis, Catecholamines metabolism, Pheochromocytoma diagnosis
Abstract

Biological diagnosis of pheochromocytoma is relatively easy in those cases releasing great amounts of catecholamines with strong clinical features; instead, diagnosis could be more problematic in atypical or asymptomatic familial pheochromocytoma with small tumors secreting low catecholamine amounts. Several plasma and urine adrenergic markers must be used to confirm the clinical suspicion. We have discussed the biological data of three totally asymptomatic pheochromocytomas (cases no 2, 3, 4) and one case with a very discrete clinical manifestation (no 1). Three patients had very small tumors (4, 7 and 25 g) secreting preeminently adrenaline, one patient had a 45 g adrenal incidentaloma without clinical expression. Our study shows that, in these special cases, except for an inconstant increase of adrenaline, plasma and urine catecholamines and urine VMA can be normal. The most useful markers are plasma and urine methoxyamines. However, plasma methoxyamines are the most sensitive because their increase over reference values is by far greater than in urines. Several factors may explain these findings: a low tumoral secretion, the nature of the released amine, the short half-life of catecholamines in plasma and, in some cases, the involvement of intratumoral catecholamine metabolism. Analysis of the ratio NMN/MN in plasma provides an additional diagnosis tool to reveal adrenaline secretion abnormalities.

Published
2001
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100. Lower sex hormones in men during anticipatory stress.

Author

Schulz P, Walker JP, Peyrin L, Soulier V, Curtin F, and Steimer T

Subjects
Adult, Humans, Hydrocortisone urine, Luteinizing Hormone urine, Male, Reference Values, Testosterone urine, Gonadal Steroid Hormones urine, Stress, Psychological urine
Abstract

Free cortisol, luteinizing hormone (LH), total testosterone and monoamines were measured in two successive nocturnal urine collections in 50 healthy men to assess the influence of anticipatory stress. The first collection (N-2) was two nights before and the second (N-1) was just on the night before a one-day experimental stressor consisting of participation in a one-day clinical research protocol. The mean cortisol level increased from 23.4 (N-2) to 66.6 micrograms (N-1), while mean LH level decreased from 2.68 (N-2) to 1.71 IU (N-1) and the mean testosterone level fell from 1.31 (N-2) to 0.70 microgram (N-1). There were no changes in monoamines. Inhibition of sex hormones is a relatively neglected area of stress research.

Published
1996
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