Reversible lesions of the nucleus of the solitary tract attenuate the memory-modulating effects of posttraining epinephrine

Behav Neurosci. 1993 Dec;107(6):955-62.

Abstract

Rats implanted with cannula tips placed above the nucleus of the solitary tract (NTS) were trained to obtain food pellets placed in 2 arms of a Y maze and then given a footshock in 1 arm of the maze. The rats then received bilateral injections of lidocaine or buffer into the NTS and peripheral injections of saline or epinephrine (0.01 or 0.05 mg/kg ip). Two tests were given 24 and 48 hr after training to assess retention in the presence and absence of contextual cues (the stainless steel floor) associated with the footshock training trial. Epinephrine (0.05 mg/kg) produced a significant enhancement in retention, which was attenuated by injections of lidocaine into the NTS. These findings indicate that the NTS is involved in mediating the memory-modulating effects of peripheral epinephrine and that such effects are initiated at least in part by activation of vagal afferents projecting to the NTS.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Afferent Pathways / drug effects
  • Afferent Pathways / physiology
  • Amygdala / drug effects*
  • Amygdala / physiology
  • Animals
  • Autonomic Nervous System / drug effects*
  • Autonomic Nervous System / physiology
  • Avoidance Learning / drug effects
  • Avoidance Learning / physiology
  • Brain Mapping
  • Cerebellum / drug effects
  • Cerebellum / physiology
  • Discrimination Learning / drug effects
  • Discrimination Learning / physiology
  • Epinephrine / pharmacology*
  • Lidocaine / pharmacology
  • Male
  • Medulla Oblongata / drug effects*
  • Medulla Oblongata / physiology
  • Mental Recall / drug effects*
  • Mental Recall / physiology
  • Orientation / drug effects
  • Orientation / physiology
  • Rats
  • Rats, Sprague-Dawley
  • Reaction Time / drug effects
  • Reaction Time / physiology
  • Retention, Psychology / drug effects*
  • Retention, Psychology / physiology
  • Solitary Nucleus / drug effects*
  • Solitary Nucleus / physiology
  • Vagus Nerve / drug effects
  • Vagus Nerve / physiology

Substances

  • Lidocaine
  • Epinephrine