N-硝基-L-精氨酸甲酯对隐睾下降固定术后生精细胞凋亡的影响

Effect of L-NAME on spermatogenic cell apoptosis in rats of experimental orchidopexy

目的：探讨一氧化氮合酶（NOS）抑制剂N硝基-L-精氨酸甲酯（L-NAME）对隐睾下降固定术后生精细胞凋亡的影响。方法：将雄性SD大鼠建立单侧隐睾模型。术后12d将隐睾组大鼠随机分为隐睾组、隐睾固定组、隐睾固定＋生理盐水组、隐睾固定＋L-NAME组，建立隐睾下降固定模型。术后分别于腹腔内注射生理盐水或L-NAME。术后第12天于腹腔内给药后2h大鼠尾部采血，取血清测定NO含量及NOS活性。术后第24天脱颈椎处死大鼠，TUNEL原位末端标记法结合流式细胞术检测各组右侧睾丸生精细胞凋亡。结果：隐睾组血清中NO浓度、NOS活性以及生精细胞凋亡率最高，隐睾固定组则高于假手术组，隐睾固定＋L-NAME组凋亡率低于其他隐睾固定组。结论：L-NAME降低隐睾下降固定后NO的产生，减少生精细胞凋亡，提示NOS抑制剂能提高隐睾下降固定术后睾丸的生精能力。

Objective： To investigate effect of L-NAME on spermatogenie cell apoptosis in rats of experimental orchidopexy. Methods： Seventy-five immature male Sprague-Dawley rats （22 day old） were randomly divided into two groups： sham operation and cryptorchid. Unilateral cryptorchidism was surgically induced in the rats. On the 12th day after operation, the cryptorchid rats were randomly devided into four groups： cryptorchid, orchidopexy,orchidopexy ＋ normal saline, and orchidopexy ＋L-NAME. Unilateral orchidopexy was surgically induced in the rats. The rats of orchidopexy ＋normal saline group and orchidopexy ＋L-NAME group were injected intraperitoneally normal saline and L-NAME （50 mg/kg） accordingly. The blood samples were collected for subsequent detection from the tail after injection two hours on the 12th day. The rats were sacrificed on the 24th days after the second operation. The level of spermatogenic cell apoptosis in testes were evaluated by FCM and TUNEL. Results： The level of sperraatogenic cell apoptosis,serum NO concentration and the activity of NOS in cryptorchidism rats were higher than those of the orchidopexy rats. Administration of L-NAME decreased serum NO concentration and spermatogenic cell apoptosis in rats of experimental orchidopexy. The activity of NOS was attenuated significantly by L-NAME. Conclusion： LNAME can reduce the production of NO and spermatogenic cell apoptosis, which shows that the inhibitor of NOS can promote spermatogenic capability in rats of experimental orchidopexy.