Establishment of arteriogenic erectile dysfunction rat model and its pathogenesis

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 (P0.01);the number of yawns was showed no obvious difference between two groups(P0.05).In ICP experiment,the mean amplitude of ICP in experimental group was decreased significantly compared with control group (P0.01).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.