A single brain stem substrate mediates the motivational effects of both opiates and food in nondeprived rats but not in deprived rats

Behav Neurosci. 1992 Apr;106(2):351-63. doi: 10.1037//0735-7044.106.2.351.

Abstract

Drug-naive and morphine-dependent rats both preferred places paired with morphine over unfamiliar neutral places. Morphine-dependent, but not naive, rats avoided places paired with the lack of morphine (i.e., withdrawal). Food-sated and food-deprived rats both preferred places paired with food over unfamiliar neutral places. Food-deprived, but not sated, rats avoided places paired with the lack of food (i.e., hunger). Lesions of the tegmental pedunculopontine nucleus (TPP) blocked the morphine- and food-conditioned place preferences in drug-naive and food-sated rats, respectively. TPP lesions failed to block morphine- and food-conditioned place preferences as well as morphine withdrawal-conditioned and hunger-conditioned place aversions in morphine-dependent and food-deprived rats, respectively. These results suggest that separate neural mechanisms subserve deprivation- and non-deprivation-induced motivation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Appetitive Behavior / drug effects
  • Appetitive Behavior / physiology
  • Arousal / drug effects
  • Arousal / physiology*
  • Association Learning / drug effects
  • Association Learning / physiology
  • Avoidance Learning / drug effects
  • Avoidance Learning / physiology
  • Brain Mapping
  • Brain Stem / drug effects
  • Brain Stem / physiology*
  • Feeding Behavior / drug effects
  • Feeding Behavior / physiology*
  • Food Deprivation / physiology*
  • Hunger / drug effects
  • Hunger / physiology*
  • Male
  • Morphine / administration & dosage
  • Motivation*
  • Pons / drug effects
  • Pons / physiology
  • Rats
  • Rats, Inbred Strains
  • Receptors, Opioid / drug effects
  • Receptors, Opioid / physiology*
  • Social Environment

Substances

  • Receptors, Opioid
  • Morphine