[The effect of mu-, delta- and kappa-opiate receptor agonists on the bioelectrical activity of the viscerosomatic convergent neurons in the posterior horn of the spinal cord].
The effects of the mu-agonists morphine and DAGO, the delta-agonists D-Pen2, D-Pen5-enkephaline and dalargine and the kappa-agonists U50-488H and dynophine 1-17 on the activity of the spinal dorsal horn neurons receiving both cutaneous and visceral nociceptive inputs were studied. The experiments were performed under chloralose anesthesia in flaxedyl-immobilized rats. Morphine (10(-6)-10(-5) M) and DAGO (5 x 10(-7)-10(-6)) given pneumophoretically or topically onto the spinal cord suppressed the activity evoked by cutaneous nociceptive stimulation to a greater extent than those used by the nociceptive stimulation of the colon and rectum. Intravenous morphine (3-12 mg/kg) suppressed the activity caused by somatic and visceral stimulation to approximately the same extent. The delta-agonists D-Pen2, D-Pen5-enkephaline (10(-6)-10(-5) M) and delargin (10(-6)-10(-5) M) administered pneumophoretically or locally produced the effects similar to those of mu-agonists. All these effects were concentration-dependent and naloxone-sensitive. The kappa-agonists U50-488N (10(-4) M) and dynorphine (10(-4) M) failed to suppress the nociceptive responses of convergent neurons.
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Kasparov
D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer; D000818:Animals; D003655:Decerebrate State / Q000503:physiopathology; D003864:Depression, Chemical; D004305:Dose-Response Relationship, Drug; D004745:Enkephalins / Q000494:pharmacology*; D007395:Interneurons / Q000187:drug effects* / Q000502:physiology; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D011759:Pyrrolidines / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D011957:Receptors, Opioid / Q000187:drug effects* / Q000502:physiology; D017465:Receptors, Opioid, delta / Q000187:drug effects / Q000502:physiology; D017473:Receptors, Opioid, kappa / Q000187:drug effects / Q000502:physiology; D017450:Receptors, Opioid, mu / Q000187:drug effects / Q000502:physiology; D013116:Spinal Cord / Q000187:drug effects* / Q000502:physiology; D014781:Viscera / Q000294:innervation*
D004745:Enkephalins; D011759:Pyrrolidines; D011957:Receptors, Opioid; D017465:Receptors, Opioid, delta; D017473:Receptors, Opioid, kappa; D017450:Receptors, Opioid, mu; D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer; D009020:Morphine