大鼠阴茎组织5-HT_2受体表达及其在糖尿病ED中变化的研究

目的:观察5-羟色胺2型受体(5-HT2R)在正常及糖尿病ED大鼠阴茎组织的表达及变化情况;观察糖尿病大鼠阴茎勃起功能的变化情况及阴茎海绵体病理损伤情况。方法:设立正常对照组(NC)及糖尿病组(DM)。在糖尿病造模后第4、8、12周进行APO诱导阴茎勃起试验,记录阴茎勃起次数及勃起阳性率。将12周DM组大鼠分为未发生ED组(NED)和ED组(DED)。取阴茎组织,免疫组化法测定5-HT2R的表达情况,光镜、透射电镜下观察大鼠阴茎组织病理改变。ELISA法测定血清5-HT含量。结果:1大鼠阴茎组织中5-HT2R的阳性染色分布在阴茎血管和海绵窦的内皮及平滑肌、神经纤维中。相对于血清5-HT浓度的增高,DM组大鼠阴茎5-HT2R表达较NC组明显下调(P<0.01);DED组5-HT2R表达下调较NED组更为显著(P<0.05)。2与NC组相比,DM组大鼠阴茎勃起功能明显下降。光镜、透射电镜下观察DED组大鼠阴茎海绵体存在明显病理损伤。结论:5-HT2R主要在阴茎血管和海绵窦的内皮及平滑肌、神经纤维中表达;5-HT及其2型受体在糖尿病性ED的发生中具有一定作用;糖尿病造成阴茎组织不可逆性病理损伤,严重影响大鼠阴茎勃起功能。

The expression and change of 5-HT2R in penis in the diabetic rats with erectile dysfunction

Objective：To explore the expression and change of 5-HT2Rin penis in the diabetic rat with ED;To observe the changes of erectile function and the pathological injury of penis in diabetic rat. Methods：SD rats were injected intraperitoneali with streptozotocin （35mg/kg） to make models of DM and normal rats were used as the eontrol（NC）. The APO test was used to evaluate the erectile function of each group at the fourth, eighth, twelfth week from the fourth day of injecting STZ. Rats in DM group were divided into DED group and NED group by APO test after 12 weeks of model setting. The levels of 5-HT2R were determinated by immunohistochemistry, The pathological changes of penis were observed by using light microscope and electronmicroscope. Results： 5-HT2R strong stainingwas localized in endothelium and smooth muscle of cavernous sinus and blood vessel, nerve fiber. Compared with the NC group,expression of 5-HT2R was down- regulated in DM group （F〈0.01）. Compared with the NED group,expression of 5 HTZR in DED descended significantly（P〈0.05）. The rates and frequencies of erection in DM group were significantly lower than that in NC group, conspicuous pathological injury existed in corpus cavernosum . Conclusion： 5-HT2R expresses in endothelium and smooth muscle of cavernous sinus and blood vessel, nerve fiber. 5-HT and 5-HT2R play an important role in the pathogenesis of DED. Diabetes cause inconvertible pathological damages to penis and influence erectile function acutely.