Efecto del ejercicio físico agudo sobre la distribución y el metabolismo de la vitamina A / Effect of acute physical exercise on the distribution and metabolism of vitamin A

Se evaluó el efecto del ejercio físico agudo sobre la distribución y el metabolismo de la vitamina A en un modelo experimental animal. Se estudiaron las concentraciones plasmáticas, hepaticas, renales, testiculares y de glándulas suprarrenales de la vitamina A y de sus principales formas moleculares: retinol y ésteres de retinol, en animales sometidos a ejercicio físico durante 2 h sin previo entrenamiento. Se observó una disminución en la concentración hepática y testicular de la vitamina A y un incremento de ésta en los riñones de los animales ejercitados. Se demostró, además, el incremento del catabolismo hepático del retinol bajo las condiones experimentales

Localization of inhibin in testes of human, bonnet monkey, dog and rat by immunoperoxidase technique.

Immunocytochemical study on the localization of inhibin in the testes of human, bonnet monkey, dog and rat was carried out using indirect immunoperoxidase technique, in order to investigate the cell types involved in inhibin production/storage. A positive reaction was observed in the testes of human, monkey and dog while it was negative in rat testis using specific antiserum to human testicular inhibin generated against homogeneous preparation of human testicular inhibin in our laboratory. Inhibin was found to be localized in Sertoli cells, spermatogonia and primary spermatocytes of human, monkey and dog testes. A weak positive reaction was observed in spermatids of human testis only. Interestingly, Leydig cells of human, monkey and dog testes showed positive reaction indicating presence of inhibin in these cells also.

Gonadal toxicity of short term chronic endosulfan exposure to male rats.

Endosulfan was studied for its effect on rat testicular toxicity in relation to the enzymes of androgen biosynthesis, viz. 3 beta-hydroxysteroid dehydrogenase (EC 1.1.1.145, 3 beta-HSD) and 17 beta-hydroxysteroid dehydrogenase (EC 1.1.1.64, 17 beta-HSD); cytosolic conjugation enzyme, glutathione-S-transferase (EC 2.5.1.18); and testicular as well as serum testosterone levels at the dose levels of 2.5, 5.0, 7.5 and 10 mg/kg body weight fed orally for 7 and 15 days. Organ and body weights of the treated animals did not change significantly, however, the testicular protein contents were found to be increased appreciably after 7 days treatments. The activity profile of cytosolic conjugation enzyme showed much remained low during 7 days treatment, however, the two steroidogenic enzymes showed much individual variations in response to endosulfan treatments. An overall varied response with respect to testosterone biosynthesis and its secretion to serum was observed suggesting nevertheless, a profound hormonal imbalance caused by this insecticide to male gonads on short term chronic exposures.

Effects of cyproterone acetate on the testicular function of bat (Rhinopoma kinneari Wroughton).

1-Cyproterone acetate administration (0.2 mg/day/animal for 25 days) caused widespread testicular necrosis. The lumen of the epididymides were devoid of spermatozoa. The RNA, protein, sialic acid and phosphatase enzyme activity of the testes were reduced. Serum transaminase enzyme activity was slightly changed. Haemoglobin, hematocrit, blood sugar, and blood urea levels were in the normal range. Regressed Leydig cell tissue and decreased production of RNA and sialic acid in the testes could be due to the antiandrogenic action produced by cyproterone acetate.