RESUMO
Adult male Indian house rats (Rattus rattus) were administered ethylene glycol monomethyl ether (EGME) (500 mg/kg) perorally daily for 1, 6 and 11 days and were examined after 1, 6, and 11 days, respectively. Also a recovery study was conducted for 4 and 8 weeks after the animals received 11 successive doses of EGME. EGME caused testicular lesions resulting in a severe impairment of spermatogenic elements. However, no histopathological changes of the Leydig cells or alterations in testicular steroidogenesis were noted. After 24 hours of EGME treatment, normal cellular associations were observed except stages IX-XIV, while after 11 days of such medication, stages I-XIV could not be confirmed except in few tubules. At this stage 92.47 % of the cellular associations were unidentified. It is assumed that the depletion in the germ cell populations occurred due to the maturation arrest at the zygotene stage of the spermatocytes. Sperm motility and sperm count were reduced in the treated animals. They were impaired with the advancement of treatment. The normal mounting and copulatory behavior and maintained testicular androgen levels suggested unimpaired libido. No morphological alteration could be visible in the Sertoli cells at the light microscopic level. Recovery of spermatogenesis was found after 8 weeks, indicating reversible toxicity of this dose, but the percentage of the frequency of occurrence of stage VII-VIII cellular associations failed to maintain its control level. These results showed that EGME medication induced reversible inhibition of spermatogenesis and rendered the male infertile.
