Inhibition by hydralazine of the conversion of dopamine to noradrenaline in rat atria in vitro and in vivo.
1. Hydralazine (10 to 2000 microgramol/l) produced a concentration-dependent inhibition of the conversion of (3H)-dopamine to (3H)-noradrenaline in rat isolated atria. 2. In rats treated with hydralazine (2 mg/kg, i.p.), there was an inhibition of the conversion of (3H)-dopamine to (3)-noradrenaline in the intact artia in vivo. 3. Hydralazine treatment may result in the appearance of dopamine as a significant co-transmitter in noradrenergic nerves, and this may contribute to the antihypertensive effect of hydralazine.
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D004298:Dopamine / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006325:Heart Atria / Q000187:drug effects; D006830:Hydralazine / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D009638:Norepinephrine / Q000096:biosynthesis*; D051381:Rats; D011954:Receptors, Dopamine / Q000187:drug effects; D014316:Tritium
D011954:Receptors, Dopamine; D014316:Tritium; D006830:Hydralazine; D004298:Dopamine; D009638:Norepinephrine