The<unk>  <unk>  is a biological<unk>  composed of<unk> s, which are endogenous lipid-based retrograde neurotransmitters that bind to cannabinoid receptors (CBRs), and cannabinoid receptor proteins that are expressed throughout the vertebrate central nervous<unk>  (including the brain) and peripheral nervous<unk> . The<unk>  remains under preliminary research, but may be involved in regulating physiological and cognitive processes, including fertility, pregnancy, pre- and postnatal development, various activity of immune<unk> , appetite, pain-sensation, mood, and memory, and in mediating the pharmacological effects of cannabis. The<unk>  plays an important role in multiple aspects of neural functions, including the control of movement and motor coordination, learning and memory, emotion and motivation, addictive-like behavior and pain modulation, among others. Two primary cannabinoid receptors have been identified: CB1, first cloned in 1990; and CB2, cloned in 1993. CB1 receptors are found predominantly in the brain and nervous<unk> , as well as in peripheral organs and tissues, and are the main molecular target of the endogenous partial agonist, anandamide (AEA), as well as exogenous THC, the most known active component of cannabis.<unk>  2-arachidonoylglycerol (2-AG), which was found to be two and three orders of magnitude more abundant in mammalian brain than AEA, acts as a full agonist at both CB receptors. Cannabidiol (CBD) is a phytocannabinoid that acts as a rather weak antagonist at both CBRs and a more potent agonist at TRPV1 and antagonist at TRPM8. It is also known to be a negative allosteric modulator at CB1. CBD has been found to counteract some of the negative side effects of THC.
Endocannabinoid system
Somatosensory system
Sympathoadrenal system
Neural pathway
Parasympathetic nervous system
Hypothalamic–pituitary–adrenal axis
Hypothalamic–pituitary–thyroid axis
Central pattern generator