Bulbocapnine is not a selective DA1 receptor antagonist.
Antagonist activity of bulbocapnine on DA1 versus DA2 dopamine receptors was studied simultaneously in a dog under pentobarbitone anaesthesia and without phenoxybenzamine pretreatment. Fenoldopam (SK&F 82526) injected into the renal artery was the DA1 agonist and dipropyl dopamine or piribedil injected into the femoral artery were the DA2 agonists. Both at 0.5 and 1 mg kg-1 doses intravenous bulbocapnine caused nearly equal inhibition of DA1 and DA2 dopamine receptor-mediated responses. Our results show that under these experimental conditions bulbocapnine is not a selective DA1 dopamine antagonist.
Kohli
J D
JD
Glock
D
D
Goldberg
L I
LI
D000818:Animals; D001060:Aporphines / Q000494:pharmacology*; D001552:Benzazepines / Q000494:pharmacology; D001667:Binding, Competitive / Q000187:drug effects; D004285:Dogs; D004298:Dopamine / Q000031:analogs & derivatives / Q000494:pharmacology; D018818:Fenoldopam; D010891:Piribedil / Q000494:pharmacology; D011954:Receptors, Dopamine / Q000187:drug effects*; D014665:Vasodilator Agents / Q000494:pharmacology
D001060:Aporphines; D001552:Benzazepines; D011954:Receptors, Dopamine; D014665:Vasodilator Agents; C020895:N,N-di-n-propyldopamine; D010891:Piribedil; D018818:Fenoldopam; D004298:Dopamine