This proposal was designed to examine the effects of sex and estrogen on the self-administration of intravenously (i.v.) delivered drugs in rats. Four animal models will be used to investigate acquisition, maintenance, regulation/dysregulation, and reinstatement of drug self-administration. The effects of sex and estrogen on the acquisition of heroin, methamphetamine and d, 1-3, 4-methylenedioxymethamphetamine (MDMA) self-administration will be examined using an autoshaping procedure. A progressive ratio (PR) schedule of reinforcement and a behavioral economic analysis of demand will be used to evaluate the effects of sex and estrogen on the maintenance of cocaine and heroin self-administration. Breakpoint (BP) measures obtained on a PR schedule, along with slopes and P-max values obtained from demand curves will be used to evaluate the reinforcing efficacy of several doses of cocaine and heroin. Differential access to cocaine self-administration will be used to investigate the effect of sex on the regulation/dysregulation of cocaine intake. Dose-response curves for cocaine will be obtained to examine group differences in shifts in the dose-response curves. The effect of estrogen on the reinstatement of cocaine self-administration will be examined using a priming model of drug reinstatement in which lever pressing for drug is extinguished by replacing cocaine infusions with saline infusions. Reinstatement of responding is then tested by administering a priming injection of cocaine.
|Larson, Erin B; Roth, Megan E; Anker, Justin J et al. (2005) Effect of short- vs. long-term estrogen on reinstatement of cocaine-seeking behavior in female rats. Pharmacol Biochem Behav 82:98-108|
|Roth, Megan E; Cosgrove, Kelly P; Carroll, Marilyn E (2004) Sex differences in the vulnerability to drug abuse: a review of preclinical studies. Neurosci Biobehav Rev 28:533-46|
|Carroll, Marilyn E; Lynch, Wendy J; Roth, Megan E et al. (2004) Sex and estrogen influence drug abuse. Trends Pharmacol Sci 25:273-9|
|Roth, Megan E; Carroll, Marilyn E (2004) Sex differences in the acquisition of IV methamphetamine self-administration and subsequent maintenance under a progressive ratio schedule in rats. Psychopharmacology (Berl) 172:443-9|
|Roth, Megan E; Carroll, Marilyn E (2004) Sex differences in the escalation of intravenous cocaine intake following long- or short-access to cocaine self-administration. Pharmacol Biochem Behav 78:199-207|
|Roth, Megan E; Casimir, Anne G; Carroll, Marilyn E (2002) Influence of estrogen in the acquisition of intravenously self-administered heroin in female rats. Pharmacol Biochem Behav 72:313-8|