Role of dorsal medial prefrontal cortex dopamine D1-family receptors in relapse to high-fat food seeking induced by the anxiogenic drug yohimbine

Neuropsychopharmacology. 2011 Jan;36(2):497-510. doi: 10.1038/npp.2010.181. Epub 2010 Oct 20.

Abstract

In humans, relapse to maladaptive eating habits during dieting is often provoked by stress. In rats, the anxiogenic drug yohimbine, which causes stress-like responses in both humans and nonhumans, reinstates food seeking in a relapse model. In this study, we examined the role of medial prefrontal cortex (mPFC) dopamine D1-family receptors, previously implicated in stress-induced reinstatement of drug seeking, in yohimbine-induced reinstatement of food seeking. We trained food-restricted rats to lever press for 35% high-fat pellets every other day (9-15 sessions, 3 h each); pellet delivery was accompanied by a discrete tone-light cue. We then extinguished operant responding for 10-16 days by removing the pellets. Subsequently, we examined the effect of yohimbine (2 mg/kg, i.p.) on reinstatement of food seeking and Fos (a neuronal activity marker) induction in mPFC. We then examined the effect of systemic injections of the D1-family receptor antagonist SCH23390 (10 μg/kg, s.c.) on yohimbine-induced reinstatement and Fos induction, and that of mPFC SCH23390 (0.5 and 1.0 μg/side) injections on this reinstatement. Yohimbine-induced reinstatement was associated with strong Fos induction in the dorsal mPFC and with weaker Fos induction in the ventral mPFC. Systemic SCH23390 injections blocked both yohimbine-induced reinstatement and mPFC Fos induction. Dorsal, but not ventral, mPFC injections of SCH23390 decreased yohimbine-induced reinstatement of food seeking. In addition, dorsal mPFC SCH23390 injections decreased pellet-priming-induced reinstatement, but had no effect on ongoing high-fat pellet self-administration or discrete-cue-induced reinstatement. Results indicate a critical role of dorsal mPFC dopamine D1-family receptors in stress-induced relapse to palatable food seeking, as well as relapse induced by acute re-exposure to food taste, texture, and smell.

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Animals
  • Anxiety / chemically induced
  • Anxiety / metabolism*
  • Appetite Regulation / drug effects
  • Appetite Regulation / physiology*
  • Hyperphagia / chemically induced
  • Hyperphagia / metabolism*
  • Hyperphagia / psychology
  • Male
  • Prefrontal Cortex / drug effects
  • Prefrontal Cortex / metabolism*
  • Prefrontal Cortex / physiology
  • Rats
  • Rats, Long-Evans
  • Receptors, Dopamine D1 / drug effects
  • Receptors, Dopamine D1 / metabolism*
  • Secondary Prevention
  • Stress, Psychological / chemically induced*
  • Stress, Psychological / metabolism
  • Stress, Psychological / psychology
  • Yohimbine / pharmacology*

Substances

  • Receptors, Dopamine D1
  • Yohimbine