一氧化氮合酶基因表达对实验性大鼠隐睾生殖细胞凋亡的影响

目的　研究诱生型一氧化氮合酶 (iNOS)及其mRNA表达与实验性大鼠隐睾生殖细胞发育、凋亡的关系。方法　 (1)采用SD雄性健康大鼠 16只 ,日龄 2 2天时复制单侧隐睾模型。 (2 )采用生物素 dUTP/酶标亲和素测定法检测睾丸生殖细胞凋亡。 (3)采用免疫组织化学方法检测大鼠睾丸生殖细胞中iNOS基因表达。 (4 )采用原位杂交法检测大鼠生殖细胞中iNOSmRNA的表达。结果　 (1)术后第 7天 ,与自身对侧正常睾丸相比 ,隐睾侧睾丸发生凋亡的生殖细胞数显著增加 (P <0 .0 1)。 (2 )单侧隐睾模型建立术后第 7天 ,在双侧睾丸的间质细胞、支持细胞和初级精母细胞中均可见iNOS蛋白及iNOSmRNA的弱阳性表达 ,在隐睾侧睾丸曲细精管中脱落的生殖细胞中可见iNOS蛋白及iNOSmRNA的强阳性表达。术后第 7天 ,与自身对侧正常睾丸相比 ,隐睾侧睾丸生殖细胞中iNOSmRNA表达显著增加 (P <0 .0 1)。结论　 (1)实验性大鼠隐睾可以导致睾丸生殖细胞凋亡增加。 (2 )iNOS蛋白及其mRNA的表达增加是隐睾生殖细胞凋亡增加的分子机制之一

The relationship of iNOS expression to the germ cell development and apoptosis in the rat cryptorchid

Objective To study the relationship of iNOS expression to the germ cell development and apoptosis in the rat cryptorchid.Methods (1) Immature rats(22 day-old Sprague Dawley) were subjected to unilaterally cryptorchid.(2) Germ cell apoptosis was detected by terminal-deoxynucleotidyl transferase mediated d-UTP nick end labeling(TUNEL).(3) Expression of iNOS was detected by immunohischemical SP method.(4) The dispersion characteristics of iNOS mNRA expression was investigated by In Situ Hybridization.Results (1) At the seventh day after operation,as compared to the control,the number of apoptotic germ cell in the cryptorchid was increased significantly,but its testes weight was decreased predominantly.(2) The weak expression of iNOS gene was localized to the cytoplasm of Legdig cell,Sertoli cell and primary spermatocytes in both testes,additional intense expression was detected in the cytoplasm of sloughed germ cells of tubules in the cryptorchid.At the seventh day after the operation,expression of iNOS mNRA increased predominantly in the cryptorchid than the control.Conclusions Enhanced expression of iNOS is believed to be one of the causes that increase the number of apoptotic germ cells in the rat cryptorchid.