Endocannabinoid System (ECS)
/en-doh-kuh-NAB-ih-noyd/
A lipid-based retrograde neurotransmitter system comprising endogenous cannabinoids (endocannabinoids), their receptors (CB1, CB2), and metabolic enzymes.
In Depth
The ECS was discovered in the early 1990s during research into THC's mechanism of action. It plays a central role in regulating synaptic plasticity, pain, appetite, mood, memory, immune function, and sleep. Endocannabinoids (primarily AEA and 2-AG) are synthesized on demand from membrane phospholipids and act as retrograde messengers — released from postsynaptic neurons to modulate presynaptic neurotransmitter release. The ECS is implicated in numerous disease states, making it a major therapeutic target.
Related Terms
Further Reading
More in Pharmacology
CB1 Receptor
Cannabinoid receptor type 1. A G protein-coupled receptor (GPCR) primarily expressed in the central nervous system. The primary target of THC's psychoactive effects.
CB2 Receptor
Cannabinoid receptor type 2. A GPCR primarily expressed in immune tissues and peripheral organs. Less abundant in the CNS than CB1.
Anandamide (AEA)
N-arachidonoylethanolamine. The first endocannabinoid identified. A partial agonist at CB1 and CB2 receptors, named from the Sanskrit word "ananda" meaning bliss.
2-Arachidonoylglycerol (2-AG)
The most abundant endocannabinoid in the brain. A full agonist at both CB1 and CB2 receptors.
FAAH (Fatty Acid Amide Hydrolase)
The primary enzyme responsible for degrading anandamide and other fatty acid amides. A key target for increasing endocannabinoid tone.