Meal schedule influences food restriction-induced locomotor sensitization to methamphetamine

Amanda L. Sharpe, Joshua D. Klaus, Michael J. Beckstead

Research output: Contribution to journalArticle

2 Scopus citations

Abstract

Rationale: Traditional protocols for inducing sensitization to psychostimulants use an intermittent or "binge"-like drug administration, and binge eating behavior is comorbid with drug abuse in humans. Food restriction increases the reinforcing properties and self-administration of many drugs of abuse. Objective: The present study tested the hypotheses that (1) food restriction induces sensitization to the locomotor stimulation observed in response to methamphetamine and (2) a binge-like feeding schedule during food restriction produces increased sensitization compared to equally restricted mice fed in three daily meals. Methods: Male DBA/2J mice were fed ad libitum or were food restricted to either an 8% or 16% loss of body weight. Additionally, the food-restricted mice were divided into two groups that were fed in either one meal (binge) or three equal-sized meals (meal). After the reduced body weight was stable, mice were tested for locomotor activity following saline and methamphetamine (1 mg/kg) injections. Results: Both 16% body weight loss groups exhibited sensitization to methamphetamine. Opposite to our hypothesis, the 8% meal but not the 8% binge food-restricted group demonstrated locomotor sensitization. Serum corticosterone levels were significantly higher in the meal-fed groups when compared to the binge- and ad libitum-fed groups. Conclusions: These results support a role for feeding schedule and plasma corticosterone levels in food restriction-induced enhancement of the effects of methamphetamine.

Original languageEnglish (US)
Pages (from-to)795-803
Number of pages9
JournalPsychopharmacology
Volume219
Issue number3
DOIs
StatePublished - Feb 1 2012

    Fingerprint

Keywords

  • Binge
  • Corticosterone
  • Mouse
  • Psychostimulants
  • Underfeeding

ASJC Scopus subject areas

  • Pharmacology

Cite this