Serum reproductive hormone and expression of apoptosis gene in spermatogenic cell in rats with manganese exposure

Objective To study the relationship between serum reproductive hormone level and expression of caspase-3 in spermatogenic cell in rats with manganese exposure.Methods Forty-eight male rats were randomly divided into one control group and two manganese chloride(MnCl2)(15,30 mg/kg) exposure groups.After exposed to manganese for 4 and 6 weeks,the serum testosterone(T),follicle stimulating bormone(FSH),and luteinizine hormone(LH) levels were detected with radioimmunoassay.The expression of caspase-3 in spermatogenic cells was detected with immunohistochemical methods(SABC).Results The levels of T,FSH and LH in 30 mg/kg MnCl2 groups were 2.78±0.74 nmol/L,0.44±0.03 U/L,0.19±0.02 U/L for rats wtih 4 weeks' exposure and 2.76±0.81 nmol/L,0.57±0.03 U/L,0.19±0.02 U/L for rats with 6 weeks' exposure,respectively.The percentages of caspase-3-positive cell were 65.49±11.34 and 82.65±5.26 for rats with 4 weeks and 6 weeks of manganses exposure,respectively.There existed a negative correlation between the caspase-3-positive-cell rate and serum level of T(r=-0.799,P0.01).There existed a positive correlation between the caspase-3-positive-cell rate and serum levels of FSH and LH(r=0.735,P0.01;r=0.737,P0.01).Conclusion The decrease of serum T and the increases of serum FSH and LH may be the important causes of the up-regulation of caspase-3 expression in spermatogenic cells in rats exposed to manganese.