Ultrastructural analysis of rat testes after gossypol acetic acid (GAA) treatment

Summary The present investigations were carried out to show the histological and ultrastructural alterations in rat testes 10 weeks after gossypol acetic acid treatment (dose: 30 mg gossypol acetic acid/kg/day). The morphological findings in the interstitial compartment were compared with the data from studies carried out to investigate the testosterone biosynthesis in gossypol acetic acid treated rats. No morphological changes in the epididymal and vasal epithelia were found; however, the germinal epithelial cells showed vacuolisation, pycnosis, disconnections of junctions, cytolysis and exfoliation of germ cells from the epithelium. The Sertoli cells were affected, too. Gossypol acetic acid seemed to stimulate the physiological activity pathologically; cellular organelles as mitochondria, endoplasmic reticulum, lysosomal vacuoles, pigment granules and nuclei were either enlarged in size and number or malformed in shape. The cellular contact was often restricted to spots or completely disconnected. If gossypol acetic acid was administered for a longer period of time some Sertoli cells were found to be unable to withstand the toxic stimulus, and the cells became necrotic too. In contrast to the toxic process in the germinal and Sertoli cells the Leydig cell compartment did not show any changes in fine structure, and therefore testosterone biosynthesis is presumed to be intact.