刚地弓形虫感染对雄性小鼠性激素分泌和睾丸激素受体的影响

Effect of Toxoplasma gondii on the gonadal hormone secretion and their receptors in male mice

目的 探讨刚地弓形虫感染对雄性小鼠黄体生成素（LIH）、睾酮（T）分泌的影响以及睾丸局部激素受体的改变。方法选用9～10周龄雄性BALB／c小鼠60只，随机分为正常对照组、刚地弓形虫感染组（腹腔分别注射刚地弓形虫速殖子2．5×10^3／只、5×10^3／只、1×10^4／只、2×10^4／只）及环磷酰胺阳性对照组。以放射免疫法检测小鼠血清LH、T以及睾丸局部T水平，并以免疫组织化学sABC法检测睾丸LH受体和T受体的变化。结果 血清及睾丸局部T水平随攻虫剂量增加而明显降低，同时T受体表达代偿性增高（P〈0．05），尤其在精母细胞；LH相对正常组无代偿性增高，LH受体亦无明显变化（P〉0．05）。结论 刚地弓形虫感染小鼠后可导致睾丸激素异常，使T降低并引起睾酮受体的代偿性表达增加，但对LH水平及LH受体表达影响不明显。

Objective To investigate the effect of Toxoplasma gondii on the secretion of luteinizing hormone, testosterone and their receptors in male mice. Methods Sixty male BALB/c mice（9 - 10 week old） were randomly divided into six groups： normol control group, tachyzoites infected groups （2.5 × 10^3 ,5 × 10^3, 1×10^4, and 2 × 10^4 tachyzoites injected individually）, cyclophosphamide positive control group. Radioimmunoassay was used to study the change of serum LH,T and tissue level of T in testis, and the expression of their receptors was measured using sABC immunohistochemistry method. Results Serum and local T decreased significantly as the injected dose increased, while its receptors increased（ P 〈 0.05 ）, especially in spermatocytes ; LH and its receptors didn＇ t increase compared to normal （ P 〉 0.05 ）. Conclusion Toxoplasma gondii infection could lead to testis hormone abnormality. Toxoplasma gondii resulted in decrease of T and increase of T receptors compensatively, while no significant changes in LH and its receptors.