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Biomedical subjects

J Jawny

Publications and source records attributed to J Jawny.

6 recordsLinked to original sources
PubMed1987

Relative binding affinity at metribolone androgenic binding sites of various antiandrogenic agents.

Sebaceous glands are androgen sensitive structures with activity reduced by antiandrogens. We characterized the relative binding affinity of cyproterone acetate, 17 alpha-propyl-mesterolone, spironolactone (canrenoic acid), ethisterone and dexamethasone by means of the competitive binding analysis at metribolone (R1881) androgen binding sites. Using the DCC-assay (dextran-coated charcoal absorption) with the Scatchard plot and saturation analysis we quantified R1881 androgen binding sites from sebaceous glands situated in the ventral side of the pinna of the Syrian hamster. As parameters for ligand affinity at these binding sites served the ligand concentration for 50% displacement of 3H-labelled synthetic steroid R1881 in constant concentrations. The in vitro measurements of the used steroids were compared to the biologic sebosuppressive effect in vivo. 17 alpha-Propylmesterolone showed the highest affinity at the androgenic binding site followed by ethisterone, cyproterone acetate and spironolactone. The results, however, do not admit an interpretation about the mode of action of the given substances, which display their biologic activity either after systemic or topic administration. In vivo distribution problems and metabolizing procedures might be due to this discrepancy.

Androgen Antagonists↗
PubMed1984

17 alpha-Propylmesterolone (SH 434): an antiandrogenic sebosuppressive substance not influencing circulating testosterone concentrations. Experimental studies in Syrian hamsters.

17 alpha-Propylmesterolone is a new synthetic 5 alpha-reduced steroid with a propyl group in C-17 position and a methyl group in the A ring. The antiandrogenic action of 17 alpha-propylmesterolone on the sebaceous glands, testes weights and plasma testosterone concentrations were examined in the animal model of the Syrian hamster. The substance was given systemically (3, 5 or 10 mg/kg) and topically (3 or 5 mg/kg). 17 alpha-propylmesterolone reduced both sebaceous gland size and sebogenesis significantly in a dose-dependent manner. The topical administration was more effective than the systemic treatment. There was no influence of 17 alpha-propylmesterolone on testosterone concentration in plasma or testes weights although a diminished capacity or absence of free cytoplasmatic androgen receptor sites was detected in the sebaceous glands of the systematically or topically treated Syrian hamster. 17 alpha-Propylmesterolone exerts a potent topical sebosuppressive effect in the animal model. These findings should give rise to human studies and clinical trials.

Androgen Antagonists↗
PubMed1984

Sensitivity and optimal performance in steroid receptor analysis.

The application of various mathematical models for the identification of binding parameters in steroid receptor studies is discussed. In contrast to the usual statistical error considerations a deterministic error analysis based on the Euclidian norm and condition numbers is included. The predicted sensitivity behaviour with respect to data scattering is in good agreement with the experimental results.

Animals↗
PubMed1983

Steroid hormone receptors and their relevance for sebum production in the sebaceous gland ear model of the Syrian hamster.

We determined the capacity of steroid hormone receptors in the sebaceous glands of intact nontreated, castrated, with testosterone substituted castrated male, intact female, and intact with testosterone substituted female animals using the animal ear model of the Syrian hamster. The steroid hormone binding capacity was compared with the sebaceous gland areas and sebogenesis. Intact male animals showed large sebaceous follicles, a high sebogenesis rate, and high capacity for sexual hormone binding proteins. In castrated males, the sebaceous gland areas and sebogenesis were both diminished, and androgen and estrogen receptors were decreased. When the castrated males were substituted with testosterone propionate, the sebaceous glands showed large volumes, high sebum production, and androgen binding activity again. In female animals having small sebaceous follicles and a low rate of sebogenesis, testosterone propionate enlarged the sebaceous glands and increased sebogenesis and the capacity of androgen binding. One can conclude from these data that testosterone is not only the main hormone for sebum production but also induces the synthesis of its own receptor.

Animals↗