锰对雄性小鼠血清性激素水平的影响

目的 探讨锰暴露对雄性小鼠血清性激素分泌的影响。 方法 选用健康雄性昆明小鼠48只,随机分为对照组和低、中、高染锰组。各组小鼠分别腹腔注射生理盐水、12.5、25.0、50.0 mg/kg MnCl2,注射容量5 ml/kg,每天染毒1次,持续14 d,最后一天染毒24 h后处死小鼠,测量体重、睾丸和附睾的重量,腹主动脉采血,离心后取血清用酶联免疫试剂盒检测促性腺激素释放激素(gonadotropin-releasing hormone,GnRH)、卵泡刺激素(folide-stimulating hormone,FSH)、黄体生成素(luteinizing hormone,LH)和睾酮(testosterone,T)的水平。HE染色观察下丘脑神经元细胞组织形态的改变。 结果 与对照组相比,各染锰组小鼠体重、睾丸和附睾脏器系数差异无统计学意义(P>0.05),而高锰组血清中GnRH、FSH和LH含量显著升高至68.22 ng/L、11.43 U/L、2 055.82 pg/ml(P<0.05),T水平明显降低至81.25 nmol/L(P<0.05)。HE染色发现对照组可见结构清楚,排列规整,核膜清晰,染锰组逐渐形态紊乱,胞体皱缩,细胞周围间隙增大。 结论 锰暴露可引起雄性小鼠血清性激素分泌异常以及下丘脑组织形态受损,GnRH、FSH、LH明显升高,睾酮降低。

Effects of manganese on serum sex hormone levels in male mice

Objective To study the effects of manganese exposure on serum sex hormone secretion in male mice. Methods Forty-eight Kunming male mice were randomly divided into the control group and the low-, medium- and high-dose MnCl2-treated groups. The control group was intraperitoneally injected with saline, while the low-, medium- and high-dose MnCl2-treated groups were intraperitoneally injected with 12.5 mg/kg, 25 mg/kg and 50 mg/kg respectively. All administration was given at a dose of 5 ml/kg body weight per mouse per day for fourteen consecutive days. All the mice were sacrified 24 hours after the final injection, and indexes of body weight, testis and epididymis were tested. The collected abdominal aortic blood was centrifugated, and the serum levels of gonadotropin-releasing hormone (GnRH), folide-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone (T) were detected by ELISA kit. HE staining was performed to observe the morphologic changes of hypothalamus neurons. Results No statistically significant differences were found in the body weight and organ coefficients of testis and epididymis between the control group and each MnCl2-treated group (P>0.05). The serum levels of GnRH, FSH and LH in the high-dose MnCl2-treated group were significantly increased to 68.22 ng/L, 11.43 U/L and 2,055.82 pg/ml respectively (P<0.05), while the T level was significantly declined to 81.25 nmol/L(P<0.05). HE staining revealed that the control group had clear structure, regular arrangement and clear nuclear membrane, while the MnCl2-treated groups gradually appeared morphological disorder, the shrunken cell body and the increased space around the cells. Conclusions Exposure to manganese can cause abnormal serum hormone secretion and impaired hypothalamic morphology in male mice. The serum levels of GnRH, FSH and LH are significantly increased, while the serum level of testosterone is decreased.