肾上腺素能受体β2和胆碱能受体M1在小鼠睾丸的表达定位及功能研究

Study on the Expression and Functions of Adrenergic Receptor β2 and Muscarinic Acetylcholine Receptor M1 in Mouse Testis

旨在研究肾上腺素能受体β2和胆碱能受体M1在小鼠睾丸组织的表达定位及其生理功能。采用RTPCR方法检测β2受体和M1受体mRNA在小鼠睾丸不同发育时期的表达变化;免疫组织化学方法研究β2受体和M1受体在小鼠睾丸的表达定位;通过体外细胞培养方法研究睾丸间质细胞β2受体和M1受体的生理功能。结果表明:β2受体和M1受体mRNA在小鼠睾丸不同发育时期均显著表达;β2受体和M1受体主要在睾丸间质细胞表达;10-5和10-6 mol·L-1经递质NE和Ach均能显著促进小鼠睾丸间质瘤细胞MLTC-1的增殖(P<0.05),β2受体阻断剂布托沙明(Buto)和M1受体阻断剂哌吡氮平(Pire)均能阻断NE和Ach的促增殖作用(P<0.05);NE和Ach均能明显抑制MLTC-1细胞3β-HSD mRNA的表达,其阻断剂Buto和Pire均能阻断其作用效果;NE可明显促进雌激素受体α(ERα)mRNA的表达,而Ach可明显促进ERβ的表达,但其阻断剂Buto和Pire并不能阻断NE和Ach促进ERα和ERβmRNA表达的作用效果。综上表明,NE和Ach调节睾丸间质细胞的数量和雄激素的合成,主要是通过分布于睾丸间质细胞的功能受体β2受体和M1受体介导的,但NE和Ach调节雌激素受体ERα和ERβ的表达并不受β2受体和M1受体的介导。

The experiment was conducted to study the expression and functions of adrenergic re- ceptor β2 （β2AR） and muscarinic acetylcholine receptor MI （M1R） in mouse testis. The expres- sion of β2AR and M1R mRNA in mouse testis was analysed by method of RT-PCR at different de- velopmental stages. Expression and localization of β2AR and MIR in mouse testis were examined by immunohistochemistry. The mouse Leydig tumor cells-1 （MLTC-1） were cultured in vitro to study the functions of β2AR and M1R. The results showed that β2AR and M1R mRNA obviously expressed in mouse testis at different developing stages. β2AR and M1R mostly localized in Leydig cells of testis. NE and Ach improved the proliferation of MLTC-1 in the concentration of 10^-3 mol · L^-1 and 10^-6 mol · L^-1 （P〈0.05）. β2AR blocker butoxamine （Buto） and M1R blocker pirenzepine （Pire） both blocked the effects of NE and Ach（P%0. 05）. NE and Ach obviously reduced the expression of 3β-HSD mRNA in MLTC-1, and the β2AR blocker Buto and M1R blocker Pire halted the effects by blocking 132AR and MIR. NE improved the expression of ERa mRNA, but Ach enhanced the expression of ERβ mRNA, receptor blocker Buto and Pire didn＇t block the effects of NE and Ach. The results indicated that the functions of NE and Ach regulating the proliferation of Leydig cells and synthesis of testosterone were mediated by β2AR and M1R, but the effects of NE and Ach on the ex- pression of ERa and ERβ were not mediated by β2AR and M1R.