Lobeline does not serve as a reinforcer in rats.
RATIONALE: Previous results demonstrated that pretreatment with lobeline attenuates d-methamphetamine self-administration in rats. OBJECTIVE: The present experiments determined if lobeline serves as a reinforcer, if it decreases d-methamphetamine-induced reinstatement of d-methamphetamine self-administration, and if it activates the mesolimbic and nigrostriatal dopamine (DA) pathways in Sprague-Dawley male rats. METHODS: The ability of intravenous (IV) lobeline (0.015-0.15 mg/kg per infusion) to engender responding and the ability of lobeline (0.015 and 0.05 mg/kg per infusion) to substitute for d-methamphetamine was determined using the self-administration paradigm. Experiments were also performed to determine if lobeline (1.0 and 3.0 mg/kg) reinstates responding for d-methamphetamine or alters the ability of d-methamphetamine (1.0 mg/kg per infusion) to reinstate responding following extinction. The effect of lobeline (3.0 mg/kg) or d-methamphetamine (1.0 and 3.0 mg/kg) on DA and dihydroxyphenylacetic acid (DOPAC) levels in the nucleus accumbens and striatum were also determined. RESULTS: Lobeline was not self-administered and did not substitute for d-methamphetamine. Also, lobeline did not reinstate responding for d-methamphetamine following extinction nor did it alter d-methamphetamine-induced reinstatement. Furthermore, lobeline did not alter DA or DOPAC levels in the either the nucleus accumbens or striatum. CONCLUSIONS: Taken together, the present results indicate that lobeline decreases d-methamphetamine self-administration by decreasing reward, not by acting as a substitute reinforcer.[1]References
- Lobeline does not serve as a reinforcer in rats. Harrod, S.B., Dwoskin, L.P., Green, T.A., Gehrke, B.J., Bardo, M.T. Psychopharmacology (Berl.) (2003) [Pubmed]
Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenesOpen Access LicencePrivacy PolicyTerms of Useapsburg
