Effects of GTP and sodium on rat striatal dopamine receptors labeled with lisuride.
[3H]Lisuride binding to rat striatal membranes appeared to be stereospecifically displaced by the dopamine antagonist butaclamol. Sodium increased the number of [3H]lisuride binding sites (Bmax) without changing the dissociation constant (Kd). GTP did not affect [3H]lisuride binding characteristics, either with or without sodium. These results suggest that dopamine receptor sites labeled by lisuride are at least in part sodium-dependent, possibly the D2-receptors not involved in adenylate cyclase stimulation.
D000818:Animals; D001058:Apomorphine / Q000378:metabolism; D003342:Corpus Striatum / Q000187:drug effects* / Q000378:metabolism; D046508:Culture Techniques; D004873:Ergolines / Q000378:metabolism*; D006160:Guanosine Triphosphate / Q000494:pharmacology*; D007700:Kinetics; D008090:Lisuride / Q000378:metabolism*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects* / Q000378:metabolism; D012964:Sodium / Q000494:pharmacology*
D004873:Ergolines; D011954:Receptors, Dopamine; D006160:Guanosine Triphosphate; D012964:Sodium; D008090:Lisuride; D001058:Apomorphine