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Rat oral mucosa microsomal Δ4-3-ketosteroid-5α-A-ring reductase enzyme system, reducing testosterone and 4-androstenedione, was found to be inducible by systemic administration of medroxyprogesterone acetate (MPA). MPA, when used in a mixture with testosterone and/or 4-androstenedione in vitro, acted as a competitive inhibitor of the reduction of these substrates. [ABSTRACT FROM AUTHOR]

Binding of ³H-Methyltrienolone (³H-R1881) to cytoplasmic androgen receptor protein and its translocation into nuclei in human gingiva was demonstrated. ³H-R1881 binds to androgen receptors with high affinity (Kd= 1.7- 1.9 × 10-9 M) and low capacity (10-16 fmol/mg protein). The binding was specific for DHT binding sites and was destroyed by proteolytic enzymes (pronase and trypsin). These results suggest that ³H-R1881 can be used as a ligand in combination with nonradioactive DHT to study androgen receptors in the gingiva. [ABSTRACT FROM AUTHOR]

Concentrations of testosterone, dehydroepiandrosterone, estradiol, progesterone, 17α- hydroxyprogesterone, and cortisol were measured in the saliva by radioimmunoassay. Saliva from male and cycling and postmenopausal female patients with and without periodontitis was studied. It was found that salivary concentration of progesterone was increased in all patients with periodontitis. While testosterone was significantly increased in the female diabetic and non- diabetic patients with periodontitis, no difference in its concentration was found in the saliva of non-diabetic males with and without periodontitis. Salivary dehydroepiandrosterone was also increased in postmenopausal females with periodontitis. In contrast, estradiol was significantly decreased or not measurable in all patient groups with periodontitis. The concentration Of cortisol and 17α-hydroxyprogesterone showed no significant differences in postmenopausal patients with and without periodontitis. In addition, the salivary concentration of all hormones in postmenopausal females showed circadian variation. Moreover, results obtained in postmen-opausal and ovariectomized females provided evidence for extragonadal production of sex steroid hormones in postmenopausal females. The present results suggest that there is a relationship between the altered production of sex steroid hormones and the incidence of periodontal pathology. [ABSTRACT FROM AUTHOR]

The cytoplasm and nucleus of male and female rabbit gingiva and cytoplasm of rabbit oral mucosa contain receptors capable of specifically binding progesterone and promegestone with high affinity (kd = 2.7 × 10-9 M) and low capacity (˜ 10 fmol/mg protein). The binding is sensitive to heat, is destroyed by warming to 37°C for 60 min by proteolytic enzymes (pronase and trypsin), and exhibits a pattern of competition similar to that obtained with progesterone receptors from other target tissues. These results provide evidence that rabbit gingiva and buccal mucosa may function as target tissues for progestins. [ABSTRACT FROM AUTHOR]

The metabolism of androgens (testosterone and androstenedione) has been studied in healthy and diseased human periodontal ligaments. An increased activity of 17β-oxidoreductase and 17-keto-5α-A-ring reductase and decreased activity of 17β-hydroxy-5α-A-ring reductase, 3αβ-oxidoreductase and 5β-A-ring reductase have been found in diseased periodontal ligament. [ABSTRACT FROM AUTHOR]

Systemic pretreatment of rats with 5,5'-diphenylhydantoin (DPH) or its addition into an in vitro assay increases microsomal hydroxylation of 17β-estradiol. This increase depends on the concentration of DPH in the microsomal cell compartment. [ABSTRACT FROM AUTHOR]

An increased biosynthesis of 17,β-estradiol was found by microsomes obtained from the inflamed human gingivae when compared to those from healthy and hyperplastic tissues. In contrast, binding of estradiol to cytoplasmic receptors was increased only in hyperplastic tissue and was independent of the amount of estradiol formed. [ABSTRACT FROM AUTHOR]

An assembly of a mouthstick with a magnetic end and its implements held in a stand has been described. This prosthesis may be applied in the habilitation of any disabled person who needs such a mechanical aid.

Systemic pretreatment of rats with 5,5'-diphenylhydantoin (DPH) or its addition into an in vitro assay increases microsomal hydroxylation of 17 beta-estradiol. This increase depends on the concentration of DPH in the microsomal cell compartment.

Simple and sensitive direct RIA for determination of salivary testosterone was developed by using RSL NOSOLVEX TM (125 1) kit produced by Radioassay System Laboratories (Carson, California). In addition, a relationship between salivary and serum free and total testosterone concentrations was studied in randomly selected 45 healthy subjects, 5 females on oral contraceptive pills and 28 hypertensive patients on various treatment regimens. The lowest weight of testosterone detectable by our modified method was equivalent to 1 pg/ml of saliva, taking into account analytical variability. Intra- and interassay coefficients of variation were 5.09 +/- 2.7% and 8.2 +/- 5.9% respectively. Statistically significant correlations were found between salivary and serum free testosterone (r = 0.97) and salivary and serum total testosterone concentrations (r = 0.70-0.87). The exception to this was a group of hypertensive females in which no correlation (r = 0.14) between salivary and total serum testosterone was found. It is also of interest that, while salivary testosterone was significantly increased in subjects taking oral contraceptives and most of the hypertensive patients the total serum testosterone concentration was in normal range. Our findings suggest that determination of salivary testosterone is a reliable method to detect changes in the concentration of available biologically active hormone in the circulation.

The cytoplasm of normal human male and female gingiva contains a receptor capable of specifically binding 17 beta-estradiol and moxestrol (R-2858) with high affinity (Kd = approximately 3.4 X 10(-10) M) and low capacity (4.5 fmol/mg protein). The binding is sensitive to heat (destroyed by warming to 37 C for 60 min), proteolytic enzymes (pronase, trypsin, and chymotrypsin), and exhibits a pattern of competition similar to that obtained with estrogen receptors from other target tissues. Nuclear uptake of [3H]estradiol was demonstrated by using a dry autoradiographic technique. Specific nuclear localization of [3H]estradiol was found predominantly in basal and spinous layers of gingival epithelium, stromal connective tissue cells (fibroblasts), and endothelial cells and pericytes of small blood vessels in the lamina propria. There was no difference between the Kd values in normal and diseased tissue or between the Kd values or number of binding sites and the age or sex of the patient. However, there was a difference between the amount of estrogen binding sites per mg protein in normal tissue compared to gingiva with dilantin hyperplasia. These results provide the first direct evidence that human gingiva may function as a target organ for estrogens.

The cytoplasm of normal human male and female gingiva contains a receptor capable of specifically binding 5 alpha-dihydrotestosterone (DHT). This binding has a high affinity for DHT (Kd, approximately 2.2 x 10-9 M) and a low capacity (approximately 190 fmol/mg protein). The binding is extremely heat sensitive and exhibits a pattern of competition similar to that obtained with DHT receptors from other target tissues. The demonstration of a specific DHT receptor in human gingiva provides the first direct biochemical evidence that this tissue may function as a target organ for androgens. There was no correlation between the Kd in normal tissue and gingival hyperplasia or between the Kd or number of binding sites and the age or sex of the patient. However, there sites and the age or sex of the patient. However, there was a significant difference (P less than 0.0005) between the amount of DHT-binding sites per mg protein in normal tissue as compared to gingival hyperplasia (drugs or pregnancy).

Systemic pretreatment of male rats with phenytoin (PHT) (30 mg/100 g body weight) significantly (P less than 0.001) increased mitotic frequency, shortened mitotic duration and renewal time in the basal cells of the oral epithelium. This effect of PHT was abolished by simultaneous s.c. injection of cyproterone acetate (CyA) (50 micrograms/100 g body weight) or by castration. CyA treatment of intact rats or castration further decreased mitotic frequency, prolonged mitotic duration and turnover time in the oral epithelium. The effect of castration was reversed by the simultaneous s.c. injection of testosterone propionate (Tp) (50 micrograms/100 g body weight). These results suggest that PHT effect on epithelial proliferation is mediated by a hormonal mechanism.

Product activation of 17beta-hydroxysteroid oxidoreductase for testosterone and androstenedione was established using the enzyme preparation from rat oral mucosa. It is suggested that this activation could be due to the conformational changes of the enzyme.

Systemic pretreatment of rats with diphenylhydantoin (DPH) or its addition into an in vitro assay increases 5alpha-reduction of testosterone by the oral mucosa. Enzyme kinetic studies showed that DPH binds to the enzyme and probably activates it by an allosteric mechanism.

Rat oral mucosa microsomal delta4-3-ketosteroid-5alpha-A-ring reductase enzyme system, reducing testosterone and 4-androstenedione, was found to be inducible by systemic administration of medroxyprogesterone acetate (MPA). MPA, when used in a mixture with testosterone and/or 4-androstenedione in vitro, acted as a competitive inhibitor of the reduction of these substrates.

Morphology and growth pattern of the pleomorphic adenoma are discussed. The relationship between these factors and recurrence is examined. A new technique for excision is also described. This technique is particularly useful for those tumors that extend into the soft palate.

Fracture of developing permanent canine teeth occurred in a black leopard hospitalized for lead poisoning. Spectrographic identification of lead in soft tissue at the site of injury suggests a relationship between lead insult and the developing dentition.

Soluble supernatant (cytosol) of rat oral mucosa was found to contain a factor accelerating the activity of microsomal delta4-3-ketosteroid-5alpha-reductase and 17beta-hydroxysteroid oxidoreductase enzymes metabolizing testosterone. Systemic administration of medroxyprogesterone acetate further increased this cytosolic activity.