Ascorbate injury and EDTA (or manganese) protection of D2-dopamine receptors.
Ascorbic acid, EDTA, and Mn2+ modulated neuroleptic binding to membrane receptors but not to solubilized receptors. Preincubation with ascorbic acid at 22 degrees C produced a profound time-dependent decline in [3H]spiperone binding to membrane receptors (prepared in Tris-ascorbate buffer). Ascorbate had minimal effect if introduced simultaneously with [3H]spiperone in the incubation medium, and receptor binding was performed and assayed at 0 degrees C. Binding to the solubilized receptor was not ascorbate sensitive. Both EDTA and Mn2+ blocked the ascorbate effect on membrane receptors but were without effect on solubilized receptors. The preparation and incubation buffers used for [3H]spiperone binding studies should include EDTA if ascorbate is present in the buffer.
D000818:Animals; D014150:Antipsychotic Agents / Q000378:metabolism; D001205:Ascorbic Acid / Q000494:pharmacology*; D003342:Corpus Striatum / Q000378:metabolism; D004285:Dogs; D004492:Edetic Acid / Q000494:pharmacology*; D066298:In Vitro Techniques; D008345:Manganese / Q000494:pharmacology*; D011954:Receptors, Dopamine / Q000187:drug effects* / Q000378:metabolism; D014325:Tromethamine
D014150:Antipsychotic Agents; D011954:Receptors, Dopamine; D014325:Tromethamine; D008345:Manganese; D004492:Edetic Acid; D001205:Ascorbic Acid