FATTY-ACID AMIDE HYDROLASE, THE DEGRADATIVE ENZYME FOR ANANDAMIDE ANDOLEAMIDE, HAS SELECTIVE DISTRIBUTION IN NEURONS WITHIN THE RAT CENTRAL-NERVOUS-SYSTEM

Fatty acid amide hydrolase (FAAH) is a membrane-bound enzyme activity that degrades neuromodulatory fatty acid amides, including oleamide an d anandamide. A single 2.5-kb FAAH mRNA is distributed throughout the rat CNS and accumulates progressively between embryonic day 14 and pos tnatal day 10, remains high until postnatal day 30, then decreases int o adulthood. FAAH enzymatic activity, as measured in dissected brain r egions, was well correlated with the distribution of its messenger RNA . In situ hybridization revealed profound distribution of FAAH mRNA in neuronal cells throughout the CNS. The most prominent signals were de tected in the neocortex, hippocampal formation, amygdala, and cerebell um. The FAAH distribution in the CNS suggests that degradation of neur omodulatory fatty acid amides at their sites of action influences thei r effects on sleep, euphoria, and analgesia. (C) 1997 Wiley-Liss, Inc.