The influence of the kappa agonist-spiradoline (U62066E) on the analgesic activity of some opioids at the spinal level.
Male Wistar rats were treated with morphine (MP) or pentazocine (PT) subcutaneously (sc) and then intrathecally (it) with a specific kappa receptor agonist spiradoline (U62066E). In another series of experiments methionine-(MENK) or leucine-enkephalin (LENK) were injected it with U62066E simultaneously. Then antinociceptive effect on thermal stimulus was measured 1 h using the tail immersion test. MP or LENK induced analgesia was enhanced by U62066E during the first 30 min of observation. MENK analgesic activity was potentiated by kappa receptor agonist only up to 5 min. U62066E acted biphasically on PT antinociceptive effect. These results suggest that kappa opioid receptors may participate in antinociceptive action of MP and LENK and in small degree for analgesic effect of PT and MENK at the spinal level.
Stachura
Z
Z
Department of Clinical Pharmacology, Medical Academy, Katowice, Poland.
Herman
Z S
ZS
D000698:Analgesia; D000700:Analgesics / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D004357:Drug Synergism; D004743:Enkephalin, Leucine / Q000008:administration & dosage / Q000494:pharmacology; D004744:Enkephalin, Methionine / Q000008:administration & dosage / Q000494:pharmacology; D007278:Injections, Spinal; D007279:Injections, Subcutaneous; D008297:Male; D009020:Morphine / Q000008:administration & dosage / Q000494:pharmacology*; D010423:Pentazocine / Q000008:administration & dosage / Q000494:pharmacology*; D011759:Pyrrolidines / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D017473:Receptors, Opioid, kappa / Q000819:agonists
D000700:Analgesics; D011759:Pyrrolidines; D017473:Receptors, Opioid, kappa; D004744:Enkephalin, Methionine; D004743:Enkephalin, Leucine; D009020:Morphine; C051272:spiradoline; D010423:Pentazocine