l-Glutamate reduces the affinity of [3H]N-propylnorapomorphine binding sites in striatal membranes.
l-Glutamate but not methyl-D-aspartate (NMDA) or quisqualate ( Quis ) (10(-6 M) in vitro with or without preincubation increased significantly the KD value of the [3H]N-propylnorapomorphine ( [3H]NPA) binding sites by 21 and 36% respectively in striatal membranes of rat without influencing the striatal [3H]spiperone binding sites. The number of striatal [3H]NPA binding sites was not changed by l-glutamate (10(-6) and 10(-5) M) in vitro. There may thus exist interactions between striatal glutamate receptors -- not related to excitatory amino-acid receptors of the NMDA or the QUIS type -- and high affinity striatal DA receptors.
D000818:Animals; D000978:Antiparkinson Agents / Q000378:metabolism*; D001058:Apomorphine / Q000031:analogs & derivatives* / Q000378:metabolism; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D001665:Binding Sites / Q000187:drug effects; D002462:Cell Membrane / Q000378:metabolism; D003342:Corpus Striatum / Q000378:metabolism* / Q000648:ultrastructure; D005971:Glutamates / Q000494:pharmacology*; D018698:Glutamic Acid; D008297:Male; D016202:N-Methylaspartate; D009467:Neuromuscular Depolarizing Agents / Q000494:pharmacology; D010069:Oxadiazoles / Q000494:pharmacology; D016318:Quisqualic Acid; D051381:Rats; D011919:Rats, Inbred Strains; D013134:Spiperone / Q000378:metabolism
D000978:Antiparkinson Agents; D005971:Glutamates; D009467:Neuromuscular Depolarizing Agents; D010069:Oxadiazoles; D001224:Aspartic Acid; D018698:Glutamic Acid; D013134:Spiperone; C009074:N-n-propylnorapomorphine; D016202:N-Methylaspartate; D016318:Quisqualic Acid; D001058:Apomorphine