Dopamine inhibits prostaglandin F2 alpha-induced depolarization of rabbit jejunal arteries via activation of DA1-receptors.
In rabbit jejunal arteries, the membrane potential of single smooth muscle cells decreased on the application of noradrenaline 3 mumol/l. LY 171555 1 mumol/l did not change, whereas SKF 38393 10 mumol/l reversed the effect of noradrenaline. When prostaglandin F2 alpha (PGF2 alpha) was used to evoke depolarization in the presence of prazosin 0.1 mumol/l, rauwolscine 1 mumol/l and propranolol 1 mumol/l, both SKF 38393 10 mumol/l and dopamine 10 mumol/l repolarized the membrane. SCH 23390 1 mumol/l antagonized the effects of SKF 38393 10 mumol/l and dopamine 10 mumol/l. Thus, the change in membrane potential is mediated by a DA1-receptor.
Illes
P
P
Department of Pharmacology, University of Freiburg, Federal Republic of Germany.
Nörenberg
W
W
D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D000818:Animals; D001158:Arteries / Q000187:drug effects; D001552:Benzazepines / Q000494:pharmacology; D015237:Dinoprost / Q000037:antagonists & inhibitors*; D004298:Dopamine / Q000494:pharmacology*; D015259:Dopamine Agents / Q000494:pharmacology; D018492:Dopamine Antagonists; D004873:Ergolines / Q000494:pharmacology; D005260:Female; D066298:In Vitro Techniques; D007583:Jejunum / Q000187:drug effects; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000378:metabolism*; D009638:Norepinephrine / Q000494:pharmacology; D019257:Quinpirole; D011817:Rabbits; D011954:Receptors, Dopamine / Q000187:drug effects*
D001552:Benzazepines; D015259:Dopamine Agents; D018492:Dopamine Antagonists; D004873:Ergolines; D011954:Receptors, Dopamine; D019257:Quinpirole; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D015237:Dinoprost; D004298:Dopamine; D009638:Norepinephrine