title: Morphine and clonidine oral self-administration: a study in morphine dependent or abstinent rats.
abstract: The ability of morphine and of clonidine to support self-administration has been evaluated in morphine dependent or abstinent rats, using an orally reinforced operant technique (F.R. 20). It was found that: Morphine drinking can function as a reinforcer of an operant response both in dependent and abstinent rats. The bitter taste of morphine becomes a secondary reinforcer for rats usually working for the alkaloid. Clonidine supports oral self-administration in morphine abstinent, but not in morphine dependent rats. The data are in line with clinical findings and give a further evidence that oral self administration in rats can be an useful model for the analysis of drug dependence.
mesh_terms: D000818:Animals; D003000:Clonidine / Q000008:administration & dosage*; D003216:Conditioning, Operant; D006801:Humans; D008297:Male; D009020:Morphine / Q000008:administration & dosage* / Q000009:adverse effects; D009021:Morphine Dependence / Q000523:psychology*; D051381:Rats; D011919:Rats, Inbred Strains; D012646:Self Administration; D013375:Substance Withdrawal Syndrome / Q000523:psychology
chemical_list: D009020:Morphine; D003000:Clonidine