Differential association of spinal mu, delta and kappa opioid receptors with cutaneous thermal and visceral chemical nociceptive stimuli in the rat

Publikation: Bidrag til tidsskrift/Konferencebidrag i tidsskrift /Bidrag til avisTidsskriftartikelForskningpeer review

The intrathecal administration of several mu (morphine), delta (d-ala2-d-leu5-enkephalin, dimeric leu-enkephalin) and mixed mu/delta (beta-endorphin) agonists produced a dose-dependent inhibition of all cutaneous thermal (Tail Flick/Hot Plate) nociceptive responses in the rat. The kappa agonist U50488H had no analgesic potency in thermal nociceptive tests. On a visceral chemical test (writhing) and agonists exerted a powerful suppression of the response. In contrast at doses 10 to 50 times the ED50 on cutaneous thermal tests, delta agonists had no effect on the writhing response. At higher intrathecal doses, delta ligands produced flaccidity. These observations suggest the existence of three discriminable populations of opioid receptors in the spinal cord whose activation has different effects on the animals response to noxious stimuli.

OriginalsprogEngelsk
TidsskriftLife Sciences
Vol/bind33 Suppl 1
Sider (fra-til)653-6
Antal sider4
ISSN0024-3205
StatusUdgivet - 1983

Se relationer på Aarhus Universitet Citationsformater

ID: 96029387