title: Phenylclindine-induced alteration in rat muscarinic cholinergic receptor regulation.
abstract: A muscarinic cholinergic receptor binding profile was performed on 3 separate regions of the rat brain following administration of the drug phencyclidine (10 mg/kg, twice a day) for 10 days. Binding assays were performed on homogenates of the hippocampus, striatum and cortex using the ligand [3H]QNB. Scatchard analysis of the binding data revealed a statistically significant decrease in the number of [3H]QNB binding sites in all phencyclidine treated animals. Binding was 22% lower in the cortex and 16% lower in the hippocampus and striatum. Phencyclidine treatment did not significantly alter the affinity of the receptor for the ligands [3H]QNB, acetylcholine or phencyclidine. This decrease in CNS muscarinic receptors could be contributing to the underlying biochemical mechanism of tolerance to the drug.
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism; D004361:Drug Tolerance; D006207:Half-Life; D010622:Phencyclidine / Q000494:pharmacology*; D011813:Quinuclidinyl Benzilate / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011950:Receptors, Cholinergic / Q000187:drug effects*; D011976:Receptors, Muscarinic / Q000187:drug effects* / Q000378:metabolism
chemical_list: D011950:Receptors, Cholinergic; D011976:Receptors, Muscarinic; D011813:Quinuclidinyl Benzilate; D010622:Phencyclidine