Evidence against a serotonin involvement in the tonic descending inhibition of nociceptor-driven neurons in the cat spinal cord.
To determine whether serotonin (5-HT) is involved in the powerful tonic descending inhibition which exists on dorsal horn nociceptor-driven neurons, their response to a noxious stimulus was tested with drugs that enhance (fluoxetine) or decrease (p-chlorophenylalanine) 5-HT synaptic activity. Neither the response with the spinal cord intact nor the enhanced response with the spinal cord cold blocked was altered by these drugs. Thus we conclude that 5-HT is not involved in this tonic descending inhibition.
D000818:Animals; D001933:Brain Stem / Q000502:physiology; D002415:Cats; D005260:Female; D008297:Male; D009433:Neural Inhibition; D009434:Neural Pathways / Q000502:physiology; D009474:Neurons / Q000502:physiology; D009619:Nociceptors / Q000502:physiology*; D012701:Serotonin / Q000502:physiology*; D013116:Spinal Cord / Q000502:physiology*
D012701:Serotonin