Microinjection of dopamine agonists into nucleus raphe magnus affects nociception in rats

Pain. 1986 Aug;26(2):259-266. doi: 10.1016/0304-3959(86)90080-1.

Abstract

Microinjection of the dopamine receptor agonist apomorphine, and to a lesser extent dopamine itself, into the nucleus raphe magnus increased tail flick latency in conscious rats. The hypoalgesia was dependent on the integrity of catecholamine-containing pathways originating near the third ventricle and was diminished by systemic depletion of hydroxytryptamine. No simple neuronal circuitry could explain all the effects observed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 5,6-Dihydroxytryptamine / administration & dosage
  • 5,6-Dihydroxytryptamine / pharmacology
  • Animals
  • Apomorphine / administration & dosage
  • Apomorphine / pharmacology*
  • Cerebral Ventricles / drug effects
  • Dopamine / administration & dosage
  • Dopamine / pharmacology*
  • Hydroxydopamines / administration & dosage
  • Hydroxydopamines / pharmacology
  • Male
  • Microinjections
  • Nociceptors / drug effects*
  • Oxidopamine
  • Periaqueductal Gray / drug effects
  • Phenylalanine / administration & dosage
  • Phenylalanine / pharmacology
  • Raphe Nuclei*
  • Rats

Substances

  • Hydroxydopamines
  • Phenylalanine
  • Oxidopamine
  • Apomorphine
  • Dopamine
  • 5,6-Dihydroxytryptamine