N-methyl-D-aspartate receptor function observed by rate of ligand dialysis from proteoliposome solution.
This study reports rate-of-dialysis of an iodinated N-methyl-D-aspartate antagonist drug, [125-I] MK-801. from solutions of lipid vesicles and from proteoliposomes containing purified membrane proteins. A 170 kd protein precipitated from proteoliposomes cross reacts with monoclonal antibodies against cloned NMDA-NR2(A) and NR2(B) subunits. Drug binding in proteoliposomes includes contributions from lipid and from protein, in addition to lipid. A significant change in drug binding was observed in proteoliposomes in response to 10 uM agonist, NMDA. Rate-of-dialysis from agonist-stimulated proteoliposomes was sensitive to perturbation by decreased aqueous ligand concentration in a manner consistent with a lipid-mediated receptor/antagonist equilibrium.
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Department of Biophysical Chemistry, University of Basel, Biocenter, Switzerland. yannis@chemie.fu-berlin.de
Volkova
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D000818:Animals; D015153:Blotting, Western; D001923:Brain Chemistry; D002417:Cattle; D002462:Cell Membrane / Q000737:chemistry; D003956:Dialysis / Q000295:instrumentation*; D007700:Kinetics; D008024:Ligands; D011510:Proteolipids / Q000737:chemistry*; D016194:Receptors, N-Methyl-D-Aspartate / Q000737:chemistry* / Q000502:physiology
D008024:Ligands; D011510:Proteolipids; D016194:Receptors, N-Methyl-D-Aspartate; C020485:proteoliposomes