Fatty acid amide hydrolase (FAAH) is a serine hydrolase with a major role in the hydrolysis of endocannabinoids. It is composed of an N-terminal transmembrane domain, a catalytic domain containing an amidase signature sequence, a polyproline sequence, and a monotopic membrane binding domain. FAAH is localized to microsomal and mitochondrial membranes and is highly expressed in the CNS but can also be found in peripheral tissues such as lung, gastrointestinal tract, kidney, liver, bladder, prostate, and testis. It primarily catalyzes the inactivation of the endogenous endocannabinoid arachidonoyl ethanolamide (AEA; ) via hydrolysis to arachidonic acid and ethanolamine but has broad substrate selectivity towards fatty acid amides, including oleamide, N-acyltaurines, and other N-acylethanolamines. Genetic or pharmacologic knockdown of FAAH increases levels of AEA and dampens pain sensitivities and inflammatory endpoints in rodent models of inflammatory pain, allergic contact dermatitis, inflammatory bowel disease, and neuropathic pain.
