Anabolic-androgenic steroids: In cell culture.

Testosterone and related steroids at physiological concentrations positively stimulate in cell culture a number of reactions in a variety of tissues from different species of animals. Cells maintained in cell culture provide a means to study toxic effects in target organs and also the mechanism of action of these steroids.

Anabolic-androgenic steroids: in cell culture.

Testosterone and related steroids at physiological concentrations positively stimulate in cell culture a number of reactions in a variety of tissues from different species of animals. Cells maintained in cell culture provide a means to study toxic effects in target organs and also the mechanism of action of these steroids.

History, chemistry and pharmacodynamics of anabolic-androgenic steroids.

It had been known for centuries that castration resulted in the loss of certain secondary male sex characteristics. The first inkling as to the cause of these changes were provided in 1849 by a prevention of the regression of the comb and wattles of capons by implantation of testis into the abdominal cavity of the castrated rooster. The results were correctly interpreted that the testis secreted a substance into the blood to regulate the development and maintenance of the male characteristics.

Metabolites of testosterone: significance in the vital economy.

Testosterone is metabolized by practically every tissue in the body to a large variety of related steroids. The metabolites vary with each tissue and appear to be formed to meet the specific needs of the particular tissue and animal. The many biologic actions of testosterone do not change in parallel in the various metabolites.

Conversion of testosterone and androstenedione to 5 beta-androstanes by adult male hamster liver cytosol.

The incubation of [4-14C]testosterone with adult male hamster liver cytosol at pH 6.7 yielded 5 beta-androstane-3 alpha, 17 beta-diol and small quantities of 5 beta-androstane-3 beta, 17 beta-diol, 17 beta-hydroxy-5 beta-androstan-3-one, 3 alpha-hydroxy-5 beta-androstan-17-one and androstenedione. The use of [4-14C]androstenedione as substrate yielded the same 5 beta-metabolites and also testosterone and a trace of epitestosterone.

Purification and properties of 17 beta-hydroxy-C19-steroid dehydrogenases of adult male guinea pig kidney.

The 17 beta-hydroxy-C19-steroid dehydrogenase activity of adult male guinea pig kidney was separated into one isolated and two contiguous enzymatically pure fractions by submitting the cytosol to (NH4)2SO4 (40-80% saturation) precipitation, Sephadex G-75 filtration, and DEAE-Sephadex A-50 and CM-Sephadex C-50 chromatography. Further DEAE-Sephadex A-50 and CM-Sephadex C-50 chromatography separated eight isozymes, which were divided into four groups in accordance with their behavior on chromatography and mobility on gel electrophoresis. The molecular weights of the purified enzymes were identical by Sephadex filtration (33,000) and SDS gel electrophoresis (34,000).

17beta-Hydroxy-C19-steroid dehydrogenases from male guinea pig liver. Purification and characterization.

One major and six minor 17beta-hydroxy-C19-steroid dehydrogenases were isolated each in a highly pure form from male adult guinea pig liver by a combination of gel filtration and ion exchange chromatography. Molecular weight, amino acid composition, sugar content, number of sulfhydryl groups. NH2-terminal amino acid, isoelectric point, substrate specificity, pH optima, Km values, and inhibitory effect of other steroids were studied.

Androgen regulation of transferase II activity in the mouse kidney.

Castration of adult male mice reduced the ability of the transferase factors of the kidney to stimulate amino acid incorporation by polysomes in vitro. The administration of testosterone propionate (TP) to the mice for 11 days greatly increased the activity of the transferase fraction. The changes occurred only in transferase II.

Free amino acids of sex organs of the mouse: regulation by androgen.

Male mice were castrated at 2 mo and a pellet of testosterone propionate was implanted subcutaneously 2 wk later. Mice were killed after 11 days and tissue extracts were analyzed. All the common 20 amino acids were present in widely varying concentrations.