Differential effect of beta-adrenergic receptor antagonism in basolateral amygdala on reconsolidation of aversive and appetitive memories associated with morphine in rats

Addict Biol. 2014 Jan;19(1):5-15. doi: 10.1111/j.1369-1600.2012.00443.x. Epub 2012 Mar 28.

Abstract

Positive and negative emotional experiences induced by addictive drugs play an important role in the development of dysfunctional drug-related memory, which becomes resistant to extinction and contributes to high rate of relapse. Those memories may undergo a process called reconsolidation that in some cases can be disrupted by pharmacological treatment. The basolateral amygdala (BLA) has been shown to mediate the reconsolidation of drug-related appetitive memory, but its role in withdrawal-related aversive memory remains elusive. The present study used conditioned place preference (CPP) and conditioned place aversion (CPA) paradigms to investigate the role of BLA and its noradrenergic receptors in reconsolidation of morphine-associated emotional memory in rats. We found that inhibition of protein synthesis in BLA disrupted the reconsolidation of morphine CPP (m-CPP) and CPA related to morphine withdrawal (m-CPA). A high dose of the β-noradrenergic receptor antagonist propranolol (3 µg) in BLA-impaired reconsolidation of m-CPA but not m-CPP, whereas a low dose (0.3 µg) was ineffective. In contrast, neither low nor high doses of the α-noradrenergic receptor antagonist phentolamine (1 or 10 µg) blocked the reconsolidation of m-CPP and m-CPA. In addition, infusion of propranolol (3 µg) into nucleus accumbens after retrieval of either m-CPP or m-CPA did not affect its reconsolidation. The findings indicate that appetitive and aversive addictive memories share common neural substrates in BLA, but the specific neurotransmitter mechanism on reconsolidation of morphine-associated negative and positive memories can be dissociable.

Keywords: Appetitive and aversive memory; basolateral amygdala; morphine; noradrenergic receptors; place conditioning; reconsolidation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenergic alpha-Antagonists / administration & dosage
  • Adrenergic alpha-Antagonists / pharmacology
  • Adrenergic beta-Antagonists / administration & dosage
  • Adrenergic beta-Antagonists / pharmacology*
  • Amygdala / drug effects*
  • Amygdala / physiopathology
  • Analysis of Variance
  • Animals
  • Anisomycin / administration & dosage
  • Appetitive Behavior / drug effects
  • Appetitive Behavior / physiology
  • Avoidance Learning / drug effects
  • Avoidance Learning / physiology
  • Choice Behavior / drug effects
  • Conditioning, Psychological / physiology
  • Dose-Response Relationship, Drug
  • Male
  • Memory / drug effects
  • Memory / physiology*
  • Microinjections
  • Morphine / pharmacology*
  • Morphine Dependence / psychology
  • Narcotics / pharmacology*
  • Nucleus Accumbens / drug effects
  • Nucleus Accumbens / physiopathology
  • Phentolamine / administration & dosage
  • Phentolamine / pharmacology
  • Propranolol / administration & dosage
  • Propranolol / pharmacology*
  • Protein Synthesis Inhibitors / administration & dosage
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Adrenergic, beta / drug effects
  • Receptors, Adrenergic, beta / physiology*
  • Recurrence
  • Substance Withdrawal Syndrome / psychology

Substances

  • Adrenergic alpha-Antagonists
  • Adrenergic beta-Antagonists
  • Narcotics
  • Protein Synthesis Inhibitors
  • Receptors, Adrenergic, beta
  • Anisomycin
  • Morphine
  • Propranolol
  • Phentolamine