A new relaxant on human corpus cavernosum: Ferulago syriaca root extract

Abstract

In vitro effects of the extract of Ferulago syriaca used as an herbal medicine in Turkey on human corpus cavernosum were demonstrated. Corpus cavernosum tissue was collected from patients that penile prosthesis implantation had been applied to. Relaxing effect in organ bath was searched for by adding increasing dosages of the extract on tissue strips that were contracted with phenylephrine. It was repeated with incubating separately with NG-nitro-L-arginine methyl ester (L-NAME) (NO-synthesis inhibitor) and oxadiazolo[4,3-α]quinoxalin-1one (ODQ) (selective guanilate cyclase inhibitor), respectively. In addition, the effects of the extract were also evaluated on the relaxing responses to Electrical field stimulation (EFS), acetylcholine, forskolin, and sodium nitroprusside. Extract caused relaxing on corpus cavernosum strips in a dose-dependent manner (relaxing with ratios of 17, 41, 61, and 87%, respectively). Relaxing of the tissue with extract could be inhibited with small dosages of L-NAME, and in all dosages of ODQ (p < 0.01). While incubating the tissue strips with the extract increased the relaxing responses to acetylcholine, it had no effect on the relaxing responses to EFS, sodium nitroprusside (SNP) and forskolin. F. syriaca root extract relaxes the human corpus cavernosum in vitro markedly. It ensures this relaxing, probably by activating NO- cyclic guanosine monophosphate (cGMP) pathway. Key words: Aphrodisiacs, bornyl acetate, penile erection, plant extracts, in vitro.