Expression of proliferation cell nucleus antigen and heat-shock protein of testis in mice exposed to manganese

  Objective   To studyeffects of manganese on countof sperm and expression of prolifer ation cell nucleus antig en(PCNA)and hea-tshock protein 70(HSP70)of testis in mice.

  Methods   The mice were randomly divided into three mang anese chloride(MnCl₂)(7.5, 15, 60 mg/kg)groups and control group.Exposed to manganese for 3, 7, 14, 28, 56 days, quantity of sperm was counted.The expression of PCNA and HSP70 in testis of mice was analysed by immunohistochemical technique(S-P)and the image analysis.

  Results   The countof sperm and expression of PCNA and HSP70 of testis decreased with the increasing of dose and time exposed to manganese.The countof sperm in three groups MnCl₂ were much lower than those of control group(P < 0.05, P < 0.01, P < 0.01)28 days afterexposure, and the expression of PCNA were much lower than those of control groups(P < 0.05, P < 0.01, P < 0.01)14, 28, 56 days afterexposure.The countof sperm and expressions of PCNA of all exposed groups were correlated positively with each other(r=0.794, P < 0.01).The expression of HSP 70 in testis of 15 and 30 mg/kg groups 56 days afterexposure were much lower than those of 28 days afterexposure(P < 0.01).

  Conclusion   There are dos-eeffects and time-effectin the damage of sper matog enic functions in mice exposed to manganese.The countof sperm and expression of PCNA of all exposed groups are correlated positively with each o ther(r=0.794, P < 0.01).The increase of HSP70 expression can be induced by Mncl₂ and peaked 28 days afterexposure.