ABSTRACT
On the basis of a conditioning analysis, some drug "withdrawal symptoms" are conditional responses elicited by stimuli paired with the drug effect. Prior demonstrations of conditional elicitation of withdrawal symptoms evaluated the role of environmental cues; however, pharmacological cues also typically signal a drug effect. Within each administration, early drug onset cues (DOCs) may become associated with the later, larger drug effect (intra-administration associations). This experiment evaluated the contribution of intra-administration associations to withdrawal symptoms. The results indicated that (a). 5 mg/kg morphine elicited behavioral and thermic withdrawal symptoms in rats previously injected on a number of occasions with 50 mg/kg morphine and that (b). DOC-elicited withdrawal symptoms are not a sensitized response to the opiate but rather an associative phenomenon.
Subject(s)
Morphine/adverse effects , Morphine/pharmacology , Narcotics/adverse effects , Narcotics/pharmacology , Substance Withdrawal Syndrome/psychology , Animals , Behavior, Animal/drug effects , Body Temperature/drug effects , Conditioning, Operant/drug effects , Dose-Response Relationship, Drug , Hypothermia/physiopathology , Injections, Intraperitoneal , Male , Morphine/administration & dosage , Narcotics/administration & dosage , Rats , Rats, Sprague-Dawley , Substance Withdrawal Syndrome/physiopathologyABSTRACT
It has been reported that ibogaine interferes with somatic withdrawal reactions in rats chronically treated with morphine. The present experiments demonstrated that ibogaine also interferes with motivational withdrawal reactions and somatic withdrawal reactions in rats treated with morphine on only two occasions. On each of two conditioning trials, naloxone was administered 24 h following an injection of morphine. Four hours prior to each naloxone administration, rats were injected with either ibogaine or saline. In two experiments, ibogaine interfered with naloxone-precipitated withdrawal. In Experiment 1, ibogaine-treated rats displayed a weaker aversion to the withdrawal-paired chamber, and in Experiment 2, ibogaine-treated rats displayed fewer somatic withdrawal reactions than did saline treated rats.
