Morphine analgesia: blockade by raphe magnus lesions.
D000818:Animals; D009020:Morphine / Q000494:pharmacology* / Q000627:therapeutic use; D010146:Pain / Q000188:drug therapy; D051381:Rats; D012154:Reticular Formation / Q000187:drug effects*; D012701:Serotonin / Q000502:physiology*; D013116:Spinal Cord / Q000187:drug effects*
D012701:Serotonin; D009020:Morphine