Effects of the alpha 1-adrenoceptor antagonist R-(-)-YM12617 on isolated human penile erectile tissue and vas deferens.
The effects of the selective alpha 1-adrenoceptor antagonist, R-(-)-YM12617 (5-[2-[[2-(0-ethoxyphenoxy)ethyl]amino] propyl]-2-methoxybenzenesulphonamide HCl), were investigated in isolated human corpus spongiosum, corpus cavernosum, and vas deferens. R-(-)-YM12617 concentration dependently and competitively inhibited contractions induced by noradrenaline in human penile erectile tissue (pA2 value in corpus spongiosum = 9.92), and the drug was approximately 12 times more potent than prazosin (pA2 value = 8.83). In the vas deferens, R-(-)-YM12617 and prazosin inhibited electrically induced contractions concentration dependently, and abolished the contractions at 10(-6) and 10(-5) M, respectively. The -log IC50 values for R-(-)-YM1261 and prazosin were 8.46 and 7.50, respectively. It is concluded that R-(-)-YM12617 is a potent inhibitor of alpha 1-adrenoceptors in human penile erectile tissues and vas deferens, and that the drug, if injected intracavernosally, may be useful for the treatment of penile erectile dysfunction.
Holmquist
F
F
Department of Clinical Pharmacology, University Hospital, Lund, Sweden.
Hedlund
H
H
Andersson
K E
KE
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000368:Aged; D004558:Electric Stimulation; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects* / Q000502:physiology; D009638:Norepinephrine / Q000494:pharmacology; D010410:Penile Erection / Q000187:drug effects; D010413:Penis / Q000187:drug effects* / Q000502:physiology; D011224:Prazosin / Q000494:pharmacology; D013449:Sulfonamides / Q000494:pharmacology*; D014649:Vas Deferens / Q000187:drug effects / Q000502:physiology; D000096926:Benzenesulfonamides
D000317:Adrenergic alpha-Antagonists; D009638:Norepinephrine; D011224:Prazosin; D013449:Sulfonamides; C044648:YM 12617; D000096926:Benzenesulfonamides