1. Where are the endothelial cells located in the corpus cavernosum of the penis? The corpus cavernosum of the penis is like a large blood vessel, mainly composed of smooth muscle, endothelial cells and the microvessels that enter and exit the corpus cavernosum. The outermost layer of the corpus cavernosum is the white membrane, a layer of tough tissue; smooth muscle forms a cavernous sinus-like structure called the cavernous sinus, which is covered with a layer of vascular endothelial cells. (Take a look at the following diagram: endothelial cells are immediately attached to the surface of the inner wall of blood vessels, but in the penile corpus cavernosum vascular endothelial cells are directly attached to the surface of smooth muscle) 2, what role do endothelial cells play in penile erection and weakness? The contraction and diastole of the smooth muscle of the penile corpus cavernosum determines the opening and closing of the cavernous sinus, and also determines erection and weakness of the penis. When the smooth muscle contracts, the cavernous sinus closes, blood is squeezed out of the cavernous body, and the penis becomes weak; conversely, when the smooth muscle is diastolic, the cavernous sinus expands, blood fills up, pressure rises, and the penis becomes hard and thick. And the contraction and diastole of smooth muscle is controlled by the chemical substances secreted by endothelial cells. Therefore, it can also be said that changes in the chemical substances secreted by the vascular endothelial cells are the key to controlling the erection and weakness of the penis. 3.How do vascular endothelial cells regulate the erection and weakness of the penis? Vascular endothelial cells themselves are rich in physiological functions and can secrete many active substances. Some of these active substances can make smooth muscle contract the blood vessels, and some can make smooth muscle diastolic. For example, when sexual excitement is caused by sexual stimulation, the nerves will transmit this information to the endothelial cells, which in turn will secrete chemicals that cause smooth muscle diastole (such as nitric oxide, NO), smooth muscle diastole after the expansion of the cavernous sinuses filled with blood, the penis will be erect. And in the usual, or emotional tension and anxiety, the nerve will also transmit this information to the endothelial cells, endothelial cells will release some vasoconstrictor substances (such as norepinephrine), then the penile cavernous smooth muscle will contract, the cavernous sinus closed blood will be squeezed out of the penis and weak. 4.What are the reasons that affect the function of vascular endothelial cells? Therefore, vascular endothelial function is the key to determining good or bad erectile function, and vascular endothelial dysfunction is also a common cause of impotence. A large number of studies have also found that even young impotent patients have vascular endothelial dysfunction of varying severity. It is only that the causes of vascular endothelial dysfunction are different in young people than in older people. Some common medical diseases and bad habits are the culprits that impair endothelial function, such as hypertension, diabetes, smoking, and hyperlipidemia. Among them, obesity, high blood lipids and smoking are pathogenic factors that many people do not pay much attention to and are common reasons why impotence is not cured in many ‘healthy’ people for a long time. Of course, for vascular endothelial dysfunction there is also the problem of congenital defects.