Synthetase system

Anandamide and 2-AG are synthesized through different pathways. Anandamide is composed of a lysate of a phospholipid precursor-NAPE. This precursor is synthesized by N-acyltransferase (NAT), which catalyzes the transfer of arachidonic acid from phospholecithin to the head group of cephalin. The separation of Anandamide from NAPE is catalyzed by a special phospholipase D (PLD). Since 2-AG is a monoglyceride, its synthesis and release are different from anandamide. Its synthesis is activated by receptor-dependent phosphatidylinositol-specific phospholipase C, and is closely related to the metabolism of triacylglycerol. Activation of metabotropic receptors coupled with PLC and diglyceride (DG) lipase can increase the synthesis of 2-AG.

Degrading enzyme system

The degradation of endocannabinoids is accomplished by two special enzyme systems: fatty amide hydrolase (FAAH) and monoacylglycerol esterase (MAGL). FAAH is a membrane enzyme belonging to the serine hydrolase family. It is widely distributed in various parts of the body and has a high concentration in the brain and liver. FAAH can degrade a variety of fatty amides, such as anandamide and sleep factor oleamide. Although FAAH can inactivate 2-AG, it is MAGL that plays the main role. MAGL is also a serine hydrolase, which is distributed in the nerve endings of specific brain neurons.