Editing Erectile dysfunction (section)

==Pathophysiology==
Penile erection is managed by two mechanisms: the reflex erection, which is achieved by directly touching the penile shaft, and the psychogenic erection, which is achieved by erotic or emotional stimuli. The former involves the peripheral nerves and the lower parts of the spinal cord, whereas the latter involves the [[limbic system]] of the [[Human brain|brain]]. In both cases, an intact neural system is required for a successful and complete erection. Stimulation of the penile shaft by the [[nervous system]] leads to the secretion of [[nitric oxide]] (NO), which causes the relaxation of the smooth muscles of the [[Corpus cavernosum penis|corpora cavernosa]] (the main erectile tissue of the penis), and subsequently penile erection.  Additionally, adequate levels of [[testosterone]] (produced by the [[testes]]) and an intact [[pituitary gland]] are required for the development of a healthy erectile system. As can be understood from the mechanisms of a normal erection, impotence may develop due to hormonal deficiency, disorders of the neural system, lack of adequate penile blood supply or psychological problems.<ref name="ed-biotapublishing">{{cite book | vauthors = Shamloul R, Bella AJ | title = Erectile Dysfunction | url = https://books.google.com/books?id=elg-AwAAQBAJ&pg=PR6 | date = 2014-03-01 | publisher = Biota Publishing | isbn = 978-1-61504-653-9 | pages = 6– | access-date = 2015-10-27 | archive-date = 2023-01-10 | archive-url = https://web.archive.org/web/20230110010913/https://books.google.com/books?id=elg-AwAAQBAJ&pg=PR6 | url-status = live }}</ref>