ABSTRACT
Gossypol was found to have an inhibiting effect on spermatogenesis in animals and has been used as an antifertility agent in clinical trial. However, a very small proportion of subjects on gossypol were found to be hypokaleimia. The direct cause of it was due to renal potassium loss. The present study was designed to make an ultrastructural observation on the enzymatic activity of the membrane protein Na-K-ATPase, the so called sodium pump of renal tubular cells of rats and guinea pigs following gossypol treatment. Gossypol was administered to male animals at a dosage of 30 mg/kg body weight daily. Kidney tissues were removed at various time intervals after gossypol treatment and processed for ultra-cytochemical study and quantitative measurement of Na-K-ATPase. The results obtained were as follows.1. The enzymatic activity of Na-K-ATPase of kidney tissues was shown to decrease slightly following gossypol treatment in both rats and giunea pigs, but there was no significant difference between the gos ol treated and the control groups.2. Ultra-cytochemical observations on the localization of Na-K-ATPase demonstrated that the enzyme reactive products in renal distal convoluting tubules, ascending limbs of Henle's loop and collecting ducts desending through the cortex to the outer medulla were mainly localized to the basal plasma membranesand their retromembranous folds of the epithelial cells. A small amount of the reactive products associated with the luminal surface of the distal convoluting and collective tubules were also observed. The amount of enzyme reactive granules of the treated animals did not differ significantly from that of controls.3. The results of perfusion experiments with ouabain indicated that ouabain inhibited Na-K-ATPase specifically in renal distal convolutions, ascending limbs and collecting tubules in both the treated and control animals.4. The cytochemical reactive granules in the erythrocyte and cardiac cell membrenes decreased in number following gossypol treatment.
ABSTRACT
Objective To study the microstructural and ultrastructural changes of the epididymis of experimental varicocele in adolescent rats and it's role in infertility resulting from varicocele. Methods A varicocele model was performed in adolescent Sprague Dawley rats by partially ligating the left renal vein,the different segments of the epididymides of the rats were prepared for light and electron microscopy,the microstructure and ultrastructure of the epididymis were studied. Results There were lesions of different degree and segment specific changes in the epididymis with varicocele.Light microscopically,the main changes were interstitial vascular hyperemia,lymphocytes infiltration,sperm granuloma developed in the interstitial;The structure of the columnar epithelia was anomalies,epithelial cells degeneration,even the vacuoles appeared in the epithelial cells.The number of halo and clear cells increased.Inside the cavity of the duct,there were shedding cells,macrophage,deformed sperms and residual bodies.Electron microscopically,numerous large lysosomes,the residual bodies,the defected main cellular organelles(e.g. the endoplasmic reticulum,the mitochondrion and the Golgi complex etc.)and even large clear vacuoles were presented in the cytoplasm of principal cells.Clear cells were filled with lysosomes that made them frequently bulging into the lumen.The microvilli of the columnar epithelia were sparse and showed local defects.The thickness of the basal membrane increased.Conclusion\ The experimental varicocele in adolescent rats lead to microstructure and ultrastructure lesions in the epididymis,which may be another important reason of infertility resulting from varicocele.\;[
ABSTRACT
The present study was designed to examine the toxic effect of gossypol on the heart, liver, kidney,adrenal and testis of the Wistar rats with the electron microscope. Gossypol was administered orally at a daily dose of 30mg/kg body weight for 1-3 weeks, the tissues were secured at various time intervals and prepared for observation. It was shown that no significant ultrastructural changes could be observed in the heart muscle, kidney, and adrenal of animals fed on gossypol at the dosage that had damaged to testis. The latter demonstrated obvious degenerative changes in spermatids and spermatocytes 3 weeks following treatment and appeared to be more sensitive to the effect of gossypol poisoning. Gossypol induced distension of the endoplasmic reticulum and caused an increases in amount of smooth endoplasmic reticulum as well as lysosomes of the hepatic cells. Other subtle ultrastructural changes in the hepatic cells including the decrease of glycogen granules, displacement of ribosomes from rough endoplasmic reticulum and the distension of canaliculi biliferi were also discernible. Based on the above results, the toxic efficacy of gossypol was analysed and discussed.