RESUMO
This study aims at exploring the effect of lead exposure during pregnancy and lactation on the rat testis, which was evaluated via light and electron microscopic examination of testicular tissue, besides estimation of serum follicle stimulating hormone [FSH], luteinizing hormone [LH] and testosterone [TT] levels. Dams were intoxicated with 10 mg/kg body weight [BW]/day lead acetate throughout the gestational period and lactation. Pups were sacrificed on postnatal [PN] days 1 and 21. The weights of the body and testes, as well as serum gonadotropins and TT concentrations were significantly reduced in pups from lead-intoxicated mothers compared with their controls. Light microscopic examination of testicular samples from lead-exposed pups revealed thin-walled seminiferous tubules with significant reduction in their size. In addition, multiple vacuoles were seen within the tubules and in the interstitium, and the interstitial spaces appeared enlarged with reduced number of Leydig cells. Apoptotic bodies were found among the basal parts of the spermatogenic epithelium. Examination of testicular tissue from the same group by electron microscopy revealed more cellular details confirming the toxic effects of lead. The altered seminiferous tubules showed multiple cytoplasmic vacuoles and precipitates along the nuclear membranes in Sertoli cells. Several seminiferous tubules showed apoptotic cells with heterochromatic nuclei and dense cytoplasm, whereas other tubules appeared ensheathed by single layers of myoid cells. Leydig cells revealed cytoplasmic vacuolations and irregular nuclei with chromatin masses. The results of this study indicate that lead intoxication affected the normal development of germinal cells and disrupted the testicular structure and endocrinal functions