Microinjection of dopamine agonists into nucleus raphe magnus affects nociception in rats.
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.
D015115:5,6-Dihydroxytryptamine / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D001058:Apomorphine / Q000008:administration & dosage / Q000494:pharmacology*; D002552:Cerebral Ventricles / Q000187:drug effects; D004298:Dopamine / Q000008:administration & dosage / Q000494:pharmacology*; D006892:Hydroxydopamines / Q000008:administration & dosage / Q000494:pharmacology; D008297:Male; D008845:Microinjections; D009619:Nociceptors / Q000187:drug effects*; D016627:Oxidopamine; D010487:Periaqueductal Gray / Q000187:drug effects; D010649:Phenylalanine / Q000008:administration & dosage / Q000494:pharmacology; D011903:Raphe Nuclei; D051381:Rats
D006892:Hydroxydopamines; D010649:Phenylalanine; D016627:Oxidopamine; D001058:Apomorphine; D004298:Dopamine; D015115:5,6-Dihydroxytryptamine