Postsynaptic D1 and D2 dopamine receptors are present in rabbit renal and mesenteric arteries

Measuring adenylate cyclase activity as a biochemical index of dopamine (DA) receptors, it was found that the selective D₁ DA receptor agonist, SKF 82526, was able to stimulate the cAMP formation in rabbit renal and mesenteric arteries, an effect blocked by haloperidol and by SCH 23390. The D₂ DA receptor agonist, bromocriptine, elicited a concentration-dependent inhibition of adenylate cyclase activity in both arteries of either normal or 6-hydroxydopamine pretreated rabbits, this effect being prevented by (-)-sulpiride but not by (+)-sulpiride. These data indicate that both D₁ and D₂ postsynaptic DA receptors, associated with stimulation or inhibition of adenylate cyclase activity, are present on the wall of rabbit renal and mesenteric arteries.