Effect of urapidil on beta-adrenoceptors of rat atria.
The effects of the antihypertensive drug urapidil were studied on chronotropic responses to isoprenaline in rat isolated atria. Urapidil (1-30 microM) antagonized the responses to isoprenaline competitively, and the pA2 value was 6.05. Thus, in addition to its alpha 1-adrenoceptor blocking action for which the pA2 value is about 7, urapidil has beta-adrenoceptor blocking activity.
Verberne
A J
AJ
Rand
M J
MJ
D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects* / Q000294:innervation; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D010879:Piperazines / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011943:Receptors, Adrenergic, beta / Q000187:drug effects*
D000959:Antihypertensive Agents; D010879:Piperazines; D011943:Receptors, Adrenergic, beta; C015568:urapidil; D007545:Isoproterenol