ENZYMATIC-SYNTHESIS OF OLEAMIDE (CIS-9,10-OCTADENOAMIDE), AN ENDOGENOUS SLEEP-INDUCING LIPID, BY RAT-BRAIN MICROSOMES

The enzymatic synthesis of a novel sleep-inducing lipid, oleamide (cis -9,10-octadecenoamide), was studied using rat brain subcellular fracti ons as enzyme sources. We found that oleamide was formed from oleic ac id and ammonia on incubation with a brain homogenate. The enzyme activ ity catalyzing the formation of oleamide from oleic acid and ammonia w as highest in the microsomal fraction among the subcellular fractions. Boiled microsomes did not exhibit appreciable enzyme activity. These results strongly suggest that oleamide can be synthesized enzymaticall y in the brains of stimulated animals.