title: Effects of CCK-8 on the reinstatement of morphine-induced CPP and expression of behavioral sensitization in rats.
abstract: Cholecystokinin octapeptide (CCK-8), a neuropeptide, plays an important role in morphine dependence and several addictive behaviors. We have previously reported that CCK-8 attenuates the acquisition of morphine-induced conditioned place preference (CPP), but the possible functions of CCK-8 on drug relapse remain unclear. Here we evaluated the effects of CCK-8 on the reinstatement of extinguished morphine-induced CPP and behavioral sensitization. A single injection of 0.1 and 1μg CCK-8 (i.c.v.) significantly attenuated both drug- (morphine) and stress- (foot shock) primed reinstatement of CPP and reduced the escalated locomotor activity in reinstatement tests. Additionally, CCK-8 blocked the expression of morphine-induced behavioral sensitization. However, administration of CCK-8 (0.01, 0.1 and 1μg) alone to morphine-pretreated rats could not trigger reinstatement of CPP and had no significant effect on threshold sensitivity to foot shock. In conclusion, our study identifies a distinct inhibitory effect of CCK-8 on the reinstatement of drug-seeking behavior and provides a potential application to the medication of drug relapse.
authors: Department of Forensic Medicine, Hebei Medical University, Hebei Key Laboratory of Forensic Medicine, Shijiazhuang 050017, PR China.
authors: D
authors: D
authors: Wen
authors: G
authors: G
authors: Zang
authors: D
authors: D
authors: Sun
authors: S
authors: S
authors: Yang
authors: F
authors: F
authors: Yu
authors: S
authors: S
authors: Li
authors: C
authors: C
authors: Ma
authors: B
authors: B
authors: Cong
mesh_terms: D000818:Animals; D001245:Association Learning / Q000187:drug effects*; D003216:Conditioning, Operant / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D058999:Drug-Seeking Behavior; D005108:Extinction, Psychological / Q000187:drug effects*; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D009043:Motor Activity / Q000187:drug effects; D009294:Narcotics / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D012844:Sincalide / Q000494:pharmacology*
chemical_list: D009294:Narcotics; D009020:Morphine; D012844:Sincalide