Antinociceptive properties of intrathecal dexmedetomidine in rats

Eur J Pharmacol. 1991 Jan 10;192(2):221-5. doi: 10.1016/0014-2999(91)90046-s.

Abstract

Dexmedetomidine is a highly selective alpha 2-adrenoceptor agonist. In this study, the intrathecal administration of dexmedetomidine into the rat lumbar subarachnoid space produced dose-dependent, prolonged antinociception as measured by hot plate and tail flick testing. Intrathecal administration of 3 or 10 micrograms of dexmedetomidine increased hot plate and tail flick latencies to cutoff values within 15 min of injection. Animals receiving 1 microgram of intrathecal dexmedetomidine did not show any significant antinociception when compared to saline controls. The intrathecal administration of the alpha 2-adrenoceptor antagonist, idazoxan, ablated all measurable antinociception produced by the prior injection of 10 micrograms of dexmedetomidine.

MeSH terms

  • Adrenergic alpha-Agonists / administration & dosage
  • Adrenergic alpha-Agonists / pharmacology*
  • Adrenergic alpha-Antagonists
  • Analgesics*
  • Animals
  • Dioxanes / pharmacology
  • Idazoxan
  • Imidazoles / administration & dosage
  • Imidazoles / antagonists & inhibitors
  • Imidazoles / pharmacology*
  • Injections, Spinal
  • Male
  • Medetomidine
  • Rats
  • Rats, Inbred Strains

Substances

  • Adrenergic alpha-Agonists
  • Adrenergic alpha-Antagonists
  • Analgesics
  • Dioxanes
  • Imidazoles
  • Medetomidine
  • Idazoxan