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. 2006 Nov 17;8(4):E693–E708. doi: 10.1208/aapsj080479

Endocannabinoid mechanisms of pain modulation

Andrea G Hohmann 1,, Richard L Suplita 1
PMCID: PMC2751366  PMID: 17233533

Abstract

Cannabinoids are antinociceptive in animal models of acute, tissue injury-, and nerve injury-induced nociception. This review examines the biology of endogenous cannabinoids (endocannabinoids) and behavioral, neurophysiological, and neuroanatomical evidence supporting the notion that cannabioids play a role in pain modulation. Behavioral pharmacological approaches, in conjunction with the identification and quantification of endocannabinoids through the use of liquid and gas chromatography mass spectrometry, have providedinsight into the functional roles of endocannabinoids in pain modulation. Here we examine the distribution of cannabinoid receptors and endocannabinoid-hydrolyzing enzymes within pain modulatory circuits together with behavioral, neurochemical, and neurophysiological studies that suggest a role for endocannabinoid signaling in pain modulation. This review will provide a comprehensive evaluation of the roles of the endocannabinoids 2-arachidonoyl-glycerol and anandamide in stress-induced analgesia. These findings provide a functional framework with which to understand the roles of endocannabinoids in nociceptive processing at the supraspinal level.

Keywords: 2-arachidonoylglycerol, anandamide, CB1, fatty acid amide hydrolase, monoacylglycerol lipase, periaqueductal gray, rostral ventromedial medulla

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