title: Vascular effects of apomorphine and related compounds in the perfused rat kidney.
abstract: The renal vascular effects of aporphines and related compounds were studied on the isolated perfused rat kidney in the presence of 10(-5) M phenoxybenzamine and 10(-5) M sotalol and after contraction of the vascular bed with prostaglandin F2 alpha (10(-7) -3 X 10(-6) M). Under these conditions, (R)-(-)-apomorphine showed renal dopaminomimetic activity, i.e. renal vasodilation competitively inhibited by (+)-butaclamol (10(-8) M) but not by (-)-butaclamol (3 X 10(-8) M). It had an apparent affinity 25 times higher but a markedly lower intrinsic activity than dopamine. N-n-Propyl and trihydroxylated aporphines were less potent and the mono-10-hydroxylated aporphine was completely inactive. (S)-(+)-Bulbocapnine also showed weak dopaminomimetic activity but tetrahydropapaveroline was devoid of such an effect. (-)-N-(2-Chloroethyl)-norapomorphine (10(-5) M) irreversibly antagonised dopamine-induced renal vasodilation. At concentrations above 3 X 10(-6) M, most aporphines and tetrahydropapaveroline induced additional non-dopamine receptor related renal vasodilation.
mesh_terms: D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D001060:Aporphines / Q000494:pharmacology*; D066298:In Vitro Techniques; D007668:Kidney / Q000098:blood supply*; D008297:Male; D010477:Perfusion; D051381:Rats; D011919:Rats, Inbred Strains; D013765:Tetrahydropapaveroline / Q000494:pharmacology; D014655:Vascular Resistance / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects*
chemical_list: D001060:Aporphines; D013765:Tetrahydropapaveroline; C025935:chloroethylnorapomorphine; D001058:Apomorphine