Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Biol Sex Differ. 2011 Mar 11;2:3. doi: 10.1186/2042-6410-2-3.

Effects of a selectively bred novelty-seeking phenotype on the motivation to take cocaine in male and female rats.

Author information

  • 1Molecular and Behavioral Neuroscience Institute, University of Michigan, Ann Arbor, MI 48109, USA. jbbecker@umich.edu.

Abstract

BACKGROUND:

Gender and enhanced novelty reactivity can predispose certain individuals to drug abuse. Previous research in male and female rats selectively bred for high or low locomotor reactivity to novelty found that bred High Responders (bHRs) acquire cocaine self-administration more rapidly than bred Low Responders (bLRs) and that bHR females in particular self-administered more cocaine than the other groups. The experiments presented here aimed to determine whether an individual's sex and behavioral phenotype interact to affect motivation to take cocaine.

METHODS:

We examined motivation for taking cocaine in two experiments using a range of doses on a progressive ratio (PR) schedule of responding in bHR or bLR males and females. Additionally, we included a measure of continuing to respond in the absence of reinforcement, a feature of addiction that has been recently incorporated into tests of animal models on the basis of the criteria for substance use disorder in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. Statistical analyses were performed using PASW Statistics 18.0 software. Data were analyzed using repeated-measures analysis of variance followed by a Bonferroni correction post hoc test when applicable.

RESULTS:

We found sex differences as well as effects of novelty reactivity on the motivation to self-administer cocaine. Specifically, females demonstrated higher breaking points on the PR schedule compared with males, regardless of phenotype, and bHR males and females exhibited higher motivation than bLR animals at a number of the doses studied.

CONCLUSIONS:

An individual's sex continues to be a predisposing factor with respect to drug abuse liability and can be compounded by additional individual differences such as reactivity to novelty.

PMID:
21396095
[PubMed]
PMCID:
PMC3071306
Free PMC Article

Images from this publication.See all images (5)Free text

Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for BioMed Central Icon for PubMed Central
    Loading ...
    Write to the Help Desk