生长激素对大鼠海绵体神经移植后再生的影响

目的:研究腓肠神经移植替代损伤的双侧海绵体神经(CN)后,生长激素(GH)对大鼠勃起功能恢复的影响。方法:24只雄性SD大鼠(3~4个月,300~400 g)随机均分为2组:神经移植组(腓肠神经移植替代损伤的双侧CN);GH组(神经移植后皮下注射GH)。2个月及4个月后,CN电刺激检测大鼠阴茎勃起功能,免疫组化SP法检测阴茎海绵体内神经元型一氧化氮合酶(nNOS)神经纤维并图像分析计算阳性像素值。结果:2个月后GH组有31.25%CN对电刺激有勃起反应,较神经移植组0%差异有显著性(P<0.05),nNOS阳性神经纤维的像素值在GH组为38 971±7 692,而神经移植组为16 538±3 179,差异同样具有显著性(P<0.05);而4个月后GH组有75%的CN对电刺激有勃起反应,神经移植组43.75%的CN有反应,差异无显著性(P>0.05);nNOS阳性神经纤维的像素值分别为91 348±18 965,79 276±12 021,差异亦无显著性(P>0.05)。结论:GH能促进CN移植后的再生,有利于盆腔根治性手术后勃起功能的恢复。

Growth Hormone Enhances Regeneration of Cavernous Nerves After Their Transplantion in Rats

Objective: To investigate the effect of growth hormone(GH) on penile erection after reconstruction of cavernous nerves using sural nerve as an interposition nerve graft in rats.Methods: Twenty-four male Sprague-Dawley rats(3-4 ms of age and 300-(400 g) in weight) were randomly divided into 2 groups: nerve graft group and GH group,each electrostimulated to determine the erectile potency 2 and 4 months after nerve graft(followed by hypodermic GH injection).The nNOS-positive nerve fibers in the corpora cavernosa were examined by streptavidin-peroxidase immunohistochemistry technique(SP method).Image analysis was used to calculate the area stained in pixel.Results: Electrostimulation at 2 months produced(31.25)% of erections in the GH group but none in the grafted rats.There was a significant difference in the erection rate produced by electrostimulation between the two groups at 2 months(P<(0.05)).The pixel of the expression of nNOS-positive nerve fibers in the GH group((38 971)±(7 692)) was also greater than that of the graft group((16 538)±(3 179),P<(0.05)).At 4 months,(43.75)% of the graft group and 75% of the GH group produced erections upon electrostimulation,with no significant difference between the two groups(P>(0.05)).The pixels of the expression of nNOS-positive nerve fibers were(79 276)±(12 021) and(91 348)±(18 965),respectively(P>(0.05)).Conclusion: GH can accelerate the regeneration of cavernous nerves after bilateral nerve grafting,and GH administration may present a new physiological approach to the treatment of erectile dysfunction after radical pelvic surgery.Natl J Androl,2006,12(9):784-786,790