Stief and colleagues concluded that the rabbit did not provide a good analogue for human penile tissue, much to the relief of the rabbit community. However, the utility of sildenafil as a corpus cavernosum blood vessel relaxant was confirmed. Sort of a cross between vigour and a famous honeymoon place. In vivo, erection is mediated by neural stimulation that is nonadrenergic and noncholinergic. However, papaverine induced erections were found to result in priapism, pain, heamatoma by Cara et.
Drugs can also inhibit erectile functioning locally.
Medical conditions, including cardiovascular disease and diabetes can lead to erectile problems in some individuals. This would explain why individuals on blood thinners may have difficulty maintaining erections. Clinical studies are reasonably impressive. A large n clinical trial was reported by Goldstein et. This study employed 532 men with erectile dysfunction of organic, psychogenic and mixed causes.