Conditioned taste aversion: modulation by 5-HT receptor activity and corticosterone.
Two experiments were designed to elucidate the involvement of the hypothalamic-pituitary-adrenal axis and the 5-hydroxytryptamine (5-HT) system in the acquisition of lithium chloride-conditioned taste aversion. In Experiment 1, rats were administered either vehicle or 50 mg/kg nefazodone daily for 4 weeks. Rats were treated with 22 mg/kg of lithium chloride in order to produce conditioned taste aversion to a sucrose solution. Three days later, nefazodone completely blocked the lithium chloride-conditioned taste aversion. In Experiment 2, the effects of chronic corticosterone administration on lithium chloride-conditioned taste aversion were investigated. Twenty male rats received either corticosterone at a dose of (50 mg/kg) or vehicle injections over a period of 14 consecutive days. Lithium chloride-conditioned taste aversion was potentiated in rats treated with corticosterone. Additionally, corticosterone-treated animals required more trials to reach extinction. These results suggest the involvement of both the 5-HT system and the hypothalamic-pituitary-adrenal axis in lithium chloride-conditioned taste aversion.
Gorzalka
Boris
B
Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, British Columbia, Canada, V6T 1Z4. bgorzalka@psych.ubc.ca
Hanson
Laura
L
Harrington
Jennifer
J
Killam
Sisley
S
Campbell-Meiklejohn
Dan
D
D000284:Administration, Oral; D000818:Animals; D001362:Avoidance Learning; D003214:Conditioning, Classical; D003345:Corticosterone / Q000008:administration & dosage / Q000493:pharmacokinetics*; D005108:Extinction, Psychological; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology; D007267:Injections; D018021:Lithium Chloride / Q000008:administration & dosage / Q000009:adverse effects / Q000037:antagonists & inhibitors; D008297:Male; D010879:Piperazines; D010913:Pituitary-Adrenal System / Q000502:physiology; D051381:Rats; D020318:Rats, Long-Evans; D044282:Receptor, Serotonin, 5-HT1A / Q000502:physiology*; D044402:Receptor, Serotonin, 5-HT2A / Q000502:physiology*; D058829:Serotonin 5-HT1 Receptor Antagonists; D058826:Serotonin 5-HT2 Receptor Agonists; D012996:Solutions / Q000008:administration & dosage; D013395:Sucrose / Q000008:administration & dosage; D013649:Taste / Q000187:drug effects* / Q000502:physiology; D013997:Time Factors; D014230:Triazoles / Q000008:administration & dosage / Q000493:pharmacokinetics
D010879:Piperazines; D044402:Receptor, Serotonin, 5-HT2A; D058829:Serotonin 5-HT1 Receptor Antagonists; D058826:Serotonin 5-HT2 Receptor Agonists; D012996:Solutions; D014230:Triazoles; D044282:Receptor, Serotonin, 5-HT1A; D013395:Sucrose; C051752:nefazodone; D018021:Lithium Chloride; D003345:Corticosterone