Spinal noradrenergic neurotransmission and the analgesia induced by brief footshock.

Abstract

Antinociception induced by brief footshock as well as by 5-methoxy-N,N-dimethyltryptamine was antagonized by lesions of the descending bulbospinal noradrenergic (NA) pathways by intrathecal injections of 6-hydroxydopamine. The alpha 2-adrenoceptor antagonist, yohimbine, injected intrathecally also blocked both types of nociceptive effects in the tail-flick and hot-plate tests. 5-Methoxy-N,N-dimethyltryptamine (1 mg/kg) potentiated shock-induced antinociception and this potentiation was also antagonized by decreased NA neurotransmission. These findings suggest an important role for spinal NA innervation, and possibly alpha 2-adrenoceptors in antinociception induced by brief footshock and serotonergic receptor stimulation induced analgesia in rats.

• Authors: W Danysz, B G Minor, G Jonsson, C Post, T Archer
• Journal: Brain research (Brain Res) Vol. 365 Issue 1 Pg. 169-73 (Feb 12 1986) ISSN: 0006-8993 [Print] Netherlands
• PMID: 3004654 (Publication Type: Journal Article)

Chemical References

• Analgesics
• Hydroxydopamines
• Methoxydimethyltryptamines
• Oxidopamine

Topics

• Afferent Pathways (physiology)
• Analgesia
• Analgesics (pharmacology)
• Animals
• Electroshock
• Hydroxydopamines (pharmacology)
• Injections, Spinal
• Male
• Methoxydimethyltryptamines (pharmacology)
• Oxidopamine
• Pain (physiopathology)
• Rats
• Rats, Inbred Strains
• Spinal Cord (physiopathology)
• Synaptic Transmission