1– Δ9-tetrahydrocannabinol (Δ 9-THC), the psychoactive ingredient of cannabis (Marijuana, Hashish ) affects memory, cognition, and pain perception mainly by activating a specific
cannabinoid receptor, CB1
2– Several endogenous brain lipids, including 2-arachidonylglycerol and anandamide, have been identified as CB1 ligands.
3– These ligands are not stored, as are classic neurotransmitters, but instead are rapidly synthesized by neurons in response to depolarization upon need.
4– Activation of metabotropic receptors (eg, by acetylcholine and glutamate) can also activate the formation of 2-AG
5– The endogenous cannabinoids can function as retrograde synaptic messengers:
• They are released from postsynaptic neurons and to activate CB1 receptors on presynaptic neurons and suppressing transmitter release.