Calmodulin inhibitor trifluoperazine attenuates the development and expression of morphine-induced conditioned place preference in rats.
The effect of trifluoperazine, a calmodulin inhibitor, on morphine-induced conditioned place preference was examined in rats. Morphine (5, 10 mg/kg, i.p.) produced significant place preference for the drug-associated place. Trifluoperazine significantly suppressed the development as well as the expression of morphine-induced place preference in a dose-dependent manner, but it neither produced place preference or aversion, nor affected locomotor activity. Injection of 0.5 and 1.0 mg/kg apomorphine, a dopamine receptor agonist, did not alter the inhibition by trifluoperazine of morphine-induced place preference. Verapamil, at the dose that failed to change the place preference induced by morphine, enhanced the inhibition by trifluoperazine of morphine-induced place preference. These findings provide the first demonstration that trifluoperazine attenuates morphine-induced conditioned place preference in rats. The action of trifluoperazine might be produced through its inhibition of calmodulin, but is probably not related to dopamine receptor blockade.
Ye
Xiang-Feng
XF
Department of Neuropharmacology, National Institute on Drug Dependence, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100083, PR China.
Lu
Ying
Y
Zhang
Pan
P
Liang
Jian-Hui
JH
D000818:Animals; D001058:Apomorphine / Q000008:administration & dosage / Q000494:pharmacology; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002147:Calmodulin / Q000037:antagonists & inhibitors*; D003213:Conditioning, Psychological / Q000187:drug effects* / Q000502:physiology; D065127:Dopamine D2 Receptor Antagonists; D004305:Dose-Response Relationship, Drug; D008297:Male; D009020:Morphine / Q000008:administration & dosage / Q000494:pharmacology*; D009043:Motor Activity / Q000187:drug effects; D009294:Narcotics / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017447:Receptors, Dopamine D1 / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism; D017448:Receptors, Dopamine D2 / Q000819:agonists / Q000378:metabolism; D014268:Trifluoperazine / Q000494:pharmacology*; D014700:Verapamil / Q000494:pharmacology
D002121:Calcium Channel Blockers; D002147:Calmodulin; D065127:Dopamine D2 Receptor Antagonists; D009294:Narcotics; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D014268:Trifluoperazine; D009020:Morphine; D014700:Verapamil; D001058:Apomorphine