title: Apomorphine induced conditioned place preference and sensitization is greater in rats exposed to unpredictable chronic mild stress.
abstract: CNS stimulants are the class of the drugs that may be used to get relief from depression. Apomorphine is a D1 and D2 receptor agonist with a CNS stimulatory effect used for the treatment of Parkinson's disease is also abused. Although many drugs of abuse produce tolerance and dependence. Long term use of pshycostimulants produce reverse tolerance described as sensitization. These drugs also have a number of other beneficial effects but their therapeutic use is limited because of abuse potential. Conditioned place preference (CPP) test is used to monitor the reinforcing effect of drugs of abuse. Stress is an important factor that precipitates and potentiates addictive effects of different drugs of abuse. The present study was designed to investigate the addictive effect of apomorphine (1mg/kg) in rats previously exposed to repeated unpredictable chronic mild stress for 10 days (animal model of depression). Results from present study illustrate that unpredictable chronic mild stress potentiates the reinforcing effects of apomorphine as the number of entries and the time spent in the CPP compartment associated with drug administration is increased. Motor activity was taken as a parameter for behavioral sensitization which is induced by repeated administration of apomorphine, monitored as the number of cage crossings in light compartment of the CPP apparatus, also increased.
authors.affiliation: Neurochemistry and Biochemical Neuropharmacology Research Unit, Department of Biochemistry, University of Karachi, Pakistan.
authors.forename: Sumera
authors.initials: S
authors.lastname: Kanwal
authors.affiliation: Neurochemistry and Biochemical Neuropharmacology Research Unit, Department of Biochemistry, University of Karachi, Pakistan.
authors.forename: Huma
authors.initials: H
authors.lastname: Ikram
authors.affiliation: Neurochemistry and Biochemical Neuropharmacology Research Unit, Department of Biochemistry, University of Karachi, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Farhan
authors.affiliation: Neuroscience Research Laboratory, Dr. Panjwani Center for Molecular Medicine and Drug Research, University of Karachi, Pakistan.
authors.forename: Darakhshan Jabeen
authors.initials: DJ
authors.lastname: Haleem
mesh_terms: D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D016739:Behavior, Addictive; D001522:Behavior, Animal / Q000187:drug effects*; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D002908:Chronic Disease; D003213:Conditioning, Psychological / Q000187:drug effects*; D004195:Disease Models, Animal; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D017208:Rats, Wistar; D012054:Reinforcement, Psychology; D013315:Stress, Psychological / Q000209:etiology / Q000523:psychology*
chemical_list: D000697:Central Nervous System Stimulants; D001058:Apomorphine