[The effect of ethanol on sexual function of males and its mechanism].

Though an adequate volume of ethanol relieves nervousness and enhances sexual desire,long term and excessive intake of ethanol can induce sexual dysfunction. The reasons that ethanol results in sexual dysfunction are as follows: ethanol inhibits the hypothalamo-pituitary-testes axis and decreases serum testosterone level. The decline of smooth muscle, choline acetyltransferase and nitric oxide synthase in the penis may be responsible for it.