动脉性阴茎勃起功能障碍大鼠模型的建立及发生机制

Establishment of arteriogenic erectile dysfunction rat model and its pathogenesis

目的:建立动脉性阴茎勃起功能障碍(ED)动物模型,并探讨其发生机制。方法:选取雄性Wistar大鼠30只,通过结扎大鼠双侧髂内动脉设立实验组(n=15),采用假手术设立对照组(n=15)。饲养4周后,对2组大鼠行注射阿朴吗啡(APO)实验和电刺激海绵体神经(ICP)实验,评价其勃起功能;利用电镜观察2组大鼠阴茎海绵体平滑肌细胞的超微结构;采用免疫组织化学方法检测2组大鼠阴茎组织中一氧化氮合成酶(NOS)的表达。结果:在APO实验中实验组大鼠的勃起次数明显少于对照组(P<0.01);大鼠打哈欠次数两组之间无变化(P>0.05);在ICP实验中实验组ICP增幅明显低于对照组(P<0.01);电镜显示实验组大鼠阴茎海绵体平滑肌细胞超微结构发生基底膜增厚、细胞膜平整、空泡增多、核固缩和染色质积聚改变;免疫组织化学结果显示实验组阴茎组织中NOS染色弱于对照组。结论:采用结扎雄性大鼠双侧髂内动脉方法建立ED动物模型较为简便、可行且可靠;动脉性ED的发生与阴茎组织细胞超微结构改变和NOS低表达有关。

Objective To establish the animal model of arteriogenic erectile dysfunction （ED）and explore the pathogenesis of ED.Methods Thirty male Wistar rats were divided into two groups：experimental group（n=15）,treated with ligating rat bilateral internal arteries;control group （n=15）,treated with sham operation only. 4weeks later,the erectile function of the rats was evaluated by injecting with apomorphine （APO）and electrostimulation of cavernous nerves and recording of the intracavernous pressure（ICP）.The ultrastructures of the smooth muscle cells of cavernous of penis were observed with transmission electron microscope;the NOS level in the penis tissue was examined by NADPH diaphorase staining.Results In APO experiment,the penile erection times in experimental group were decreased significantly compared with control group （P〈0.01）;the number of yawns was showed no obvious difference between two groups（P〉0.05）.In ICP experiment,the mean amplitude of ICP in experimental group was decreased significantly compared with control group （P〈0.01）.Electron microscopy showed that in the smooth muscle cells in experimental group,there were a significantly less number of mitochondria in the cytoplasm,less number of caveolae with fingerlike processes in the plasma membrane,increased number of vacuoles in the cytoplasm compared with control group.The NOS staining in experimental group was less intense compared with control group.Conclusion It is easy,practicable and reliable to establish the arteriogenic ED rat animal model by ligating rat bilateral internal arteries.Both the changes of ultrastructures and the low NOS level in penis tissue play roles in the occurrence of ED.