Chapter 10
Cannabinoid CB2 Receptor Mechanism
ofCannabis sativa L.
Emmanuel S. Onaivi, Hiroki Ishiguro and Qing-Rong Liu
Abstract Cannabinoids and many other compounds are constituents inCannabis
sativa L., (cannabaceae) and endocannabinoids (eCBs) are the endogenous
marijuana-like substances found in animals and humans. Endocannabinoids, phy-
tocannabinoids and marijuana use activate two cannabinoid receptors (CBRs),
CB1Rs and CB2Rs that are encoded in human chromosomes 6 and 1 respectively.
New understanding in the science of cannabis botany along with medical and
biotechnological advances demonstrate that phytocannabinoids and eCBs acting on
CBRs are important regulators of various aspects of physiological, behavioral,
immunological and metabolic functions. CB2Rs were previously thought to be
predominantly expressed in immune cells in the periphery and were traditionally
referred to as peripheral CB2Rs. The neuronal and functional expression of CB2Rs
in the brain had been controversial and have been less well characterized in com-
parison with the expression of the ubiquitous CB1Rs. We and others have now
demonstrated the expression of CB2Rs in neuronal, glial and endothelial cells in the
brain, and this warrants a re-evaluation of the CNS effects of CB2Rs. In this chapter
we focused on the neurobiology of CB2Rs and describe its gene structure, regu-
lation, variation, CNS distribution and its emerging role in immuno-
endocannabinoid interactions with novel knowledge and deeper insight from the
genetic and epigenetic manipulation of CB2Rs. With the rapidly shifting landscape
on recreational, medicalization, and legalization of marijuana use, further research
will certainly provide the scientific basis to unravel the mode of action of marijuana
use and its implication on its neurological and psychiatric effects in human health
and disease. We conclude that CB2 cannabinoid receptor signaling plays an
important role in neuro-immuno-cannabinoid activity and beyond with potential
therapeutic targets in neurological and mental diseases.
E.S. Onaivi (&)Q.-R. Liu
Department of Biology, William Paterson University, Wayne, NJ 07470, USA
e-mail: [email protected]; [email protected]
H. Ishiguro
Department of Psychiatry and Clinical Ethics, University of Yamanashi,
Chuo, Yamanashi, Japan
©Springer International Publishing AG 2017
S. Chandra et al. (eds.), Cannabis sativaL. - Botany and Biotechnology,
DOI 10.1007/978-3-319-54564-6_10
227