sr-59230a and Urinary-Bladder--Overactive

To clarify the potential of TRK-380 as a drug for overactive bladder in humans by evaluating the agonistic activities for human β-adrenergic receptors (β-ARs) and the relaxing effects on isolated detrusor strips.. The agonistic activities for human β-ARs were evaluated in SK-N-MC cells (for human β(3)-ARs) and Chinese hamster ovary cells expressing human β(1)- or human β(2)-ARs using the cyclic adenosine monophosphate accumulation assay. The relaxing effects on the resting tension in isolated detrusor strips from humans, monkeys, dogs, and rats and on carbachol- or KCl-induced contractions in human detrusor strips were evaluated.. In the cyclic adenosine monophosphate accumulation assay, the agonistic activity of TRK-380 for human β(3)-ARs was potent and equivalent to that of the potent nonselective β-AR agonist isoproterenol and superior to that of selective β(3)-AR agonists, such as BRL-37344 and CL316,243. TRK-380 showed no agonistic activity for human β(1)-ARs and a weak agonistic effect on human β(2)-ARs. In isolated detrusor strips, the concentration-dependent relaxing effects of TRK-380 on the resting tension were equivalent to those of isoproterenol in humans, monkeys, and dogs but weaker than the effects in rats. The selective β(3)-AR antagonist SR59230A shifted the concentration-response curve in a concentration-dependent manner to TRK-380 for the resting tension of human detrusor strips to the right. TRK-380 had a concentration-dependent relaxing effect on the contractile responses to carbachol and KCl in human detrusor strips.. TRK-380 was a potent and selective human β(3)-AR agonist, and the isolated human detrusor relaxation was mainly mediated by activation of the β(3)-AR. Consequently, TRK-380 might be a promising compound for the treatment of overactive bladder.

Topics: Adrenergic beta-3 Receptor Antagonists; Adrenergic beta-Agonists; Animals; Cells, Cultured; Cricetinae; Cricetulus; Cyclic AMP; Dose-Response Relationship, Drug; Logistic Models; Muscle Contraction; Organ Culture Techniques; Propanolamines; Urinary Bladder; Urinary Bladder, Overactive

To examine the relaxant effects of AJ-9677, a novel beta(3)-adrenoceptor agonist, on the isolated rat, monkey and human detrusor muscle.. The isolated detrusor strips of rats, monkeys and humans were mounted in organ baths containing Krebs solution. By the cumulative addition of beta-adrenoceptor agonists (isoproterenol, AJ-9677, CL 316,243 and salbutamol in rats; isoproterenol, AJ-9677 and CL 316,243 in monkeys and humans), concentration-relaxation curves were obtained. The maximal relaxation responses and pEC(50) values were calculated. In rats, concentration-relaxation curves to isoproterenol and AJ-9677 were obtained in the presence and absence of propranolol or SR 59230A.. Isoproterenol, AJ-9677, CL 316,243 and salbutamol induced concentration-dependent relaxation in rats. The rank order of their relaxing potency in the rat detrusor muscle was AJ-9677 > isoproterenol > CL 316,243 > salbutamol. Isoproterenol and AJ-9677 also produced a concentration-dependent relaxation with high potency in monkeys and humans, whilst CL 316,243 had low relaxing potency. According to the antagonist studies in rats, propranolol and SR 59230A caused a rightward shift of the concentration-relaxation curves to isoproterenol or AJ-9677, respectively.. AJ-9677 has a high relaxant potency on the rat, monkey and human detrusor smooth muscle, and it may have the potential to treat overactive bladder.

Topics: Acetates; Adrenergic beta-Agonists; Adult; Aged; Aged, 80 and over; Animals; Dioxoles; Female; Humans; In Vitro Techniques; Indoles; Isoproterenol; Macaca fascicularis; Male; Middle Aged; Muscle Relaxation; Muscle, Smooth; Propanolamines; Propranolol; Rats; Rats, Sprague-Dawley; Urinary Bladder, Overactive