Effects of Exposure to Tributyltin Chloride during the Critical Period for Sex Differentiation on Spermatogenesis Function and Activities of Enzyme in Testis in Rats

Objective To explore the effects of exposure to tributyltin chloride(TBTC) during the critical period for sex differentiation on activities of enzymes in testis and spermatogenesis function in Wistar rats.Methods Sixteen healthy adult pregnant Wistar rats were randomly divided into four groups(5,2.5 and 1 mg/kg TBTC,vehicle control) with 4 animals per dose group.They were given doses of TBTC by gavage from days 12-20 of gestation once a day.The volume of the vehicle used was 5 ml/kg body weight.On the postnatal day(PND) 70,ten male offspring rats were randomly selected in each group and sacrificed by decapitation after weighed.The sperms in epididymis were counted and the activities of enzymes of testis [including lactate dehydrogenase(LDH),succinate dehydrogenase(SDH),acid phosphatase(ACP),nitric oxide synthase(NOS)] were detected.Several testises were chosen for the histopathological examination.Results The body weight gains of pregnant rats from days 12-20 showed no significant difference among the solvent control group and the each TBTC exposure group(P0.05).Compared with the control group,body weights gains from PND21-70 were decreased significantly in the 5 and 2.5 mg/kg group(P0.01).Cauda epididymal sperm counts increased with the increase of TBTC doses(P0.01).The activities of LDH in all treated groups and the activities of SDH in the 5 and 2.5 mg/kg TBTC group exhibited significant increase compared with the control group(P0.01).There were no significant difference in the activities of ACP and NOS between the exposure groups and the control group(P0.05).No abnormal structure of testis was observed in all exposure groups.Conclusion Exposure to TBTC during critical period for sex differentiation may decrease body gain and increase spermatogenesis and the activities of LDH and SDH.