Alpha 1-adrenoceptor blocking activities of bevantolol hydrochloride(NC-1400) and labetalol in rat isolated thoracic aorta--do they distinguish between subtypes?
1. alpha 1-adrenoceptor blocking activity of bevantolol(NC-1400) was tested in the rat thoracic aorta, comparing with that of labetalol. 2. In alpha 1-adrenoceptor blocking activity, bevantolol(NC-1400) was 1/20th as potent as labetalol. 3. The pA2 values of bevantolol(NC-1400) and labetalol estimated in the rat thoracic aorta were compared with those in the rabbit thoracic aorta, which were reported by Takayanagi et al. [Takayanagi I., Kizawa Y., Iwasaki S. and Nakagoshi A. (1987) Gen. Pharmac. 18, 87-89]. 4. The pA2 values of bevantolol(NC-1400) and labetalol were approximately 1 order of magnitude higher in rat aorta than in rabbit aorta, suggesting that both the drugs distinguish between subtypes of alpha 1-adrenoceptors.
Department of Chemical Pharmacology, Toho University School of Pharmaceutical Sciences, Chiba, Japan.
K
K
Shiraishi
M
M
Moriya
N
N
Miyake
I
I
Takayanagi
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D007741:Labetalol / Q000494:pharmacology*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D009638:Norepinephrine / Q000037:antagonists & inhibitors / Q000494:pharmacology; D011412:Propanolamines / Q000494:pharmacology*; D011817:Rabbits; D051381:Rats; D017208:Rats, Wistar; D011942:Receptors, Adrenergic, alpha / Q000378:metabolism
D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; D011942:Receptors, Adrenergic, alpha; C021148:bevantolol; D007741:Labetalol; D009638:Norepinephrine