Cannabinoid analgesia.
During the last decade, rigorous scientific methods have been applied to determine the effects of cannabinoids on nociceptive neurotransmission. Cannabinoids have been observed to markedly decrease signalling in specific neural pathways that transmit messages about pain. These effects were found to be due to the suppression of spinal and thalamic nociceptive neurons, and independent of any actions on either the motor system or sensory neurons that transmit messages related to non-nociceptive stimulation. Spinal, supraspinal, and peripheral sites of cannabinoid analgesia have been identified. The discovery of endocannabinoids raised the question of their natural role in pain. Multiple lines of evidence indicate that endocannabinoids serve naturally to suppress pain. While it is now clear that cannabinoids suppress nociceptive neurotransmission, more work is needed to establish the clinical utility of these compounds. The few human studies conducted to date produced mixed results, with more promising findings coming from studies of clinical pain as compared with experimental pain. The therapeutic potential of cannabinoids remains an important topic for future investigations.
Walker
J Michael
JM
Department of Psychology, Brown University, Providence, RI 02912, USA. j_walker@brown.edu
Huang
Susan M
SM
D000700:Analgesics / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D063385:Cannabinoid Receptor Modulators; D002186:Cannabinoids / Q000494:pharmacology* / Q000627:therapeutic use; D002490:Central Nervous System / Q000187:drug effects / Q000502:physiology; D006801:Humans; D009619:Nociceptors / Q000187:drug effects / Q000502:physiology; D010146:Pain / Q000188:drug therapy / Q000378:metabolism / Q000503:physiopathology; D010147:Pain Measurement; D017933:Peripheral Nervous System / Q000187:drug effects / Q000502:physiology; D043882:Receptors, Cannabinoid; D011955:Receptors, Drug / Q000187:drug effects / Q000378:metabolism; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology
D000700:Analgesics; D063385:Cannabinoid Receptor Modulators; D002186:Cannabinoids; D043882:Receptors, Cannabinoid; D011955:Receptors, Drug