Chronic moderate alcohol consumption induces iNOS expression in the penis: An immunohistochemical study

Aim: To investigate the effect of moderate alcohol consumption on metabolic alterations, inducible nitric oxide synthase (iNOS), immunohistochemical distribution, and morphological damage to penile erectile tissue in rats. Materials and methods: Male Wistar albino rats were divided into 2 groups. Group 1 rats (control group, n = 8) received tap water ad libitum, and group 2 rats (n = 8) were fed with 20% ethanol. Increasing levels of alcohol were given to the rats over 12 weeks. Immunohistochemistry was then performed using the avidin–biotin–peroxidase technique on 5-μm thickness tissue sections. Stained sections were examined by imaging microscope. Results: Alcohol consumption resulted in a significant increase in iNOS immunoreactivity in the penile erectile tissue. Increased iNOS expression was determined in the tunica albuginea, cavernosal smooth muscle cells, trabeculae of connective tissue, arterioles, and the urethral epithelium. Moreover, chronic alcohol consumption resulted in decreasing serum testosterone and high density lipoprotein (HDL) levels with increasing cholesterol and triglyceride levels. Conclusion: Chronic moderate alcohol consumption can affect penile erectile tissue by increasing iNOS immunoreactivity and induce histopathological damage such as penile fibrosis. These abnormalities are also related to the defense mechanism against morphological damage.