Effects of intratesticular aflatoxin B1 on rat testes and blood estrogens.

An investigation of the effects of aflatoxin B1 on rat testes and plasma estrogens is reported. A normal saline-suspended aflatoxin B1 was injected into right testes of mature Sprague-Dawley rats at doses of 0, 5, 10, 25 or 50 micrograms. Effects were evaluated by histopathological alterations of the testes and by levels of plasma estrogens estimated by a modified Dextron-Charcoal radioimmune assay. Significant gross lesions were present in testes injected with the 50 microgram dose. There was a 50% reduction in size and weight as compared to the left testis. Histological changes were dose-dependent, with minimal or no changes at 5 micrograms and maximal effects at 50 micrograms. The lesions varied from mild testicular degeneration to complete disappearance of cellular components. Interstitial cell proliferation, occasional calcification of seminiferous tubules, and absence of spermatogenesis and spermatozoa were extreme toxic effects. Estrogen concentrations in injected rats were reduced compared to those of control and normal rats. This study suggested that following intratesticular aflatoxin B1 exerts a direct toxic effect on testes with a reduction in plasma estrogen levels.