Blockade of acquisition of drug-conditioned place aversion by 5HT3 antagonists.
The effect of two 5HT3 antagonists, ICS 205-930 and MDL 72222, on drug-induced place aversion was studied in a two-compartment apparatus with a procedure including a pre-test for spontaneous preference. Naloxone (0.8 mg/kg SC), phencyclidine (2.5 mg/kg SC) and picrotoxin (2.0 mg/kg IP) paired with the preferred compartment elicited a significant place aversion. ICS 205-930 and MDL 72222 failed to modify spontaneous place preference when paired with both compartments. ICS 205-930 (30 micrograms/kg SC) paired with the preferred and, in other experiments, with the non-preferred compartment, also failed to modify spontaneous preference. ICS 205-930 (7.5, 15 and 30 micrograms/kg SC), paired with both compartments, dose-dependently reduced the place aversion induced by naloxone (0.8 mg/kg SC), phencyclidine (2.5 mg/kg SC) and picrotoxin (2.0 mg/kg IP). MDL 72222 (30 micrograms/kg SC) paired with both compartments had a similar effect. The result indicate that 5HT, via 5HT3 receptors, plays a role in the aversive properties of drug stimuli.
Acquas
E
E
Institute of Experimental Pharmacology and Toxicology, University of Cagliari, Italy.
Carboni
E
E
Garau
L
L
Di Chiara
G
G
D000818:Animals; D003216:Conditioning, Operant / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D007211:Indoles / Q000494:pharmacology; D008297:Male; D009270:Naloxone / Q000494:pharmacology; D010622:Phencyclidine / Q000494:pharmacology; D010852:Picrotoxin / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012702:Serotonin Antagonists / Q000494:pharmacology*; D014326:Tropanes / Q000494:pharmacology; D000077526:Tropisetron
D007211:Indoles; D009270:Naloxone; D010622:Phencyclidine; D010852:Picrotoxin; D012702:Serotonin Antagonists; D014326:Tropanes; D000077526:Tropisetron; C042253:bemesetron