NS-49, an α1A-adrenoceptor agonist, selectively increases intraurethral pressure in dogs

摘要: Abstract The effects of NS-49 (( R )-(−)-3′-(2-amino-1-hydroxyethyl)-4′-fluoromethane sulfonanilide hydrochloride), an α 1A -adrenoceptor-selective agonist, on intraurethral pressure and blood were investigated in anesthetized dogs. In addition, the contractile isolated dog urethra carotid artery compared with those non-selective 1 -adrenoceptor agonists. Intravenously (i.v.) administered at 0.3 μg/kg or more significantly increased a dose-dependent manner. Much higher doses needed to increase pressure. contrast, ST-1059 (1-(2′,5′-dimethoxyphenyl)-2-aminoethanol) (an active metabolite midodrine) 30 both was 11-fold selective for than ST-1059. NS-49, ST-1059, phenylephrine noradrenaline caused concentration-dependent contraction urethra. only slight even high concentrations, whereas reference drugs contractions efficacy. antagonists 5-methylurapidil WB-4101 also showed affinity -adrenoceptors inhibiting [ 3 H]prazosin binding. conclusion, -selective agonist selectively presure dogs, produced These results suggest that subtype is responsible regulation pressure, might be useful treatment stress incontinence little effect cardiovascular system.