Contribution of impulsivity and novelty-seeking to the acquisition and maintenance of MDMA self-administration.
It has been suggested that the response to novelty and impulsivity predict the latency to acquisition and maintenance of drug self-administration, respectively. The aim of this study was to examine the relationship between these two traits and (1) the latency to acquisition and (2) maintenance (drug-seeking) of 3,4-methylenedioxymethamphetamine (MDMA) self -administration. Impulsivity, measured as premature responding on the five-choice serial reaction time task (5-CSRTT), and novelty-seeking, measured as the locomotor response in a novel environment, were measured prior to self-administration. Latency to acquisition was determined as the number of test sessions required to self-administer an initial criterion of 90 infusions of 1.0 mg/kg/infusion, as well as an additional 150 infusions of 0.5 mg/kg/infusion MDMA. For some rats, the ability of MDMA [0, 5.0 or 10.0 mg/kg, intraperitoneal (IP)] to produce drug-seeking was subsequently measured, and for others, impulsivity was again measured following self-administration. Novelty-seeking was not significantly correlated with either the acquisition or drug-seeking measures of MDMA self-administration. Impulsivity was not significantly correlated with the latency to acquire self-administration of MDMA, but was significantly and positively correlated with the magnitude of MDMA-produced drug-seeking. Furthermore, MDMA self-administration produced a number of notable, but transient, deficits in the 5-CSRTT; there was an increase in omission rate and a delayed increase in premature responses in particular. These findings suggest that impulsivity, but not sensation seeking, might be a risk factor for the development of compulsive drug-seeking following withdrawal from MDMA self-administration.
School of Psychology, Victoria University of Wellington, New Zealand.
Judith
J
Bird
Susan
S
Schenk
D019969:Amphetamine-Related Disorders / Q000503:physiopathology / Q000523:psychology*; D000704:Analysis of Variance; D000818:Animals; D004195:Disease Models, Animal; D058999:Drug-Seeking Behavior / Q000187:drug effects / Q000502:physiology*; D005106:Exploratory Behavior; D006213:Hallucinogens / Q000008:administration & dosage* / Q000494:pharmacology; D006801:Humans; D007175:Impulsive Behavior; D016014:Linear Models; D008124:Locomotion / Q000502:physiology; D008297:Male; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000008:administration & dosage* / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D012054:Reinforcement, Psychology; D012646:Self Administration / Q000523:psychology; D013997:Time Factors
D006213:Hallucinogens; D018817:N-Methyl-3,4-methylenedioxyamphetamine