When we’re talking about cannabis and psychoactivity, we’re dealing exclusively with CB1 receptors, which are concentrated in the brain and the central nervous system. The difference between CBD vs. THC comes down to a basic difference in how each one interacts with the cannabinoid 1 (CB1) receptor. THC binds well with CB1 cannabinoid receptors. CBD has low binding affinity for CB1 receptors. That’s where the two diverge.
Think of it like an electrical plug connecting to a wall socket. A THC molecule is perfectly shaped to connect with CB1 receptors. When that connection happens, THC activates, or stimulates, those CB1 receptors. Researchers call THC a CB1 receptor agonist, which means THC works to activate those CB1 receptors.
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