Many receptors are part of a newly discovered part of this communication network called the endocannabinoid system (ECS), which exists in all vertebrates, including humans. The ECS plays an important role in maintaining the body’s normal way of doing things. It is involved in the development of our brain and nervous system, the way our immune system functions, appetite and digestion, cardiovascular function, bone development, pain, reproduction, memory, our sleep/wake cycles, and the regulation of stress and emotions.
One of the best-studied receptors of the ECS is cannabinoid receptor 1, or CB1. CB1 is found on the cell surface of neurons and helps modulate signalling throughout the nervous system. One of the chemical signals that unlocks the CB1 receptor is called anandamide. It has effects that are similar to some of those of THC, like euphoria.
Instead of travelling forward from one neuron to the next—the route that nerve impulses travel—anandamide is released from the post-synaptic neuron, sent backwards across the synapse, and binds to CB1 receptors on the previous neuron. This binding sends a signal into the previous neuron, telling it to stop releasing its chemical messenger (neurotransmitter), and thus dampening the message the previous neuron is sending.