Pharmacologic Effect of Phentolamine on Norepinephrine Induced Contraction of Corpus Cavernosum

Suh, Jun Kyu; Mo, Seong Jong; Kim, Young Soo; Park, Tong Choon

Abstract

An in vitro pharmacologic study was conducted to investigate the effect of phentolamine on norepinephrine induced contraction of human corpus cavernosum. The isometric muscle tension of corpus cavernosum from 4 potent volunteers were recorded after stimulation with various concentrations of norepinephrine and phentolamine. The results are summarized as follows. Contractile response of corpus cavernosum was observed to begin in the concentration of 10(-6) M and to reach maximal level in the concentration of 10(-4)M norepinephrine. Compared to it, contractile activity of corpus cavernosum to norepinephrine was observed to be gradually decreased in response to pretreatment with phentolamine from 10(-6)M to 10(-4)M. These indicate that norepinephrine causes a dose dependent contraction of corpus cavernosum and phentolamine had a relaxant effect on norepinephrine-induced contraction of corpus cavernosum in dose dependent manner.