Morphine enhances the activity of thermoreceptive cold-specific lamina I spinothalamic neurons in the cat

Brain Res. 1991 Aug 30;558(1):93-7. doi: 10.1016/0006-8993(91)90719-c.

Abstract

The possibility that morphine might differentially affect spinal neurons responsive to small-diameter thermoreceptive-specific afferents was tested. Systemic morphine enhanced a portion or all of the stimulus-response function of 7 of 9 lamina I spinothalamic tract cells specifically sensitive to cold applied to the glabrous hindpaw in the cat. This result contrasts strongly with the predominant inhibition of nociceptive lamina I neurons by morphine.

Publication types

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

MeSH terms

  • Analysis of Variance
  • Animals
  • Cats
  • Cold Temperature
  • Foot / innervation
  • Morphine / pharmacology*
  • Neural Inhibition
  • Neurons / physiology*
  • Nociceptors / drug effects
  • Sensory Receptor Cells / physiology*
  • Spinothalamic Tracts / cytology
  • Spinothalamic Tracts / physiology*
  • Thermosensing / physiology*

Substances

  • Morphine