CB 1 and CB 2 Receptor Pharmacology

Abstract

The CB1 and CB2 cannabinoid receptors (CB1R, CB2R) are members of the G protein coupled receptor (GPCR) family that were identified over 20 years ago. CB1Rs and CB2Rs mediate the effects of Δ9-tetrahydrocannabinol (Δ9-THC), the principal psychoactive constituent of marijuana and subsequently identified endogenous cannabinoids (endocannabinoids) anandamide and 2-arachidonoyl glycerol. CB1Rs and CB2Rs have both similarities and differences in their pharmacology. Both receptors recognize multiple classes of agonist and antagonist compounds and produce an array of distinct downstream effects. Natural polymorphisms and alternative splice variants may also contribute to their pharmacological diversity. As our knowledge of the distinct differences grows, we may be able to target select receptor conformations and their corresponding pharmacological responses. This chapter will discuss their pharmacological characterization, distribution, phylogeny and signaling pathways. In addition, the effects of extended agonist exposure and how that affects signaling and expression patterns of the receptors is considered.

Activation of cannabinoid receptors promote periodontal cell adhesion and migration

“…The pathophysiological effects of cannabinoids are caused by its effective components binding to cannabinoid receptors (CBs) to initiate downstream cell signalling (Howlett & Abood, ; Munro, Thomas, & Abu‐Shaar, ). Cannabinoids, including phytocannabinoids, endocannabinoids and synthetic cannabinoids, share same cannabinoid receptors (CBs) (Pertwee et al, ).…”

In silico interaction analysis of cannabinoid receptor interacting protein 1b (CRIP1b) – CB1 cannabinoid receptor

“…The two cannabinoid receptors, the CB 1 receptor and the CB 2 receptor, have been identified including multiple splice variants of CB 1 in humans [1, 2]. The CB 1 receptor is predominantly expressed in brain where it seems to play an important role in regulating analgesia, appetite, obesity, learning and memory, synaptic plasticity, substance abuse disorders, and neuro-protection [1, 3–5].…”

“…The CB 1 receptor is predominantly expressed in brain where it seems to play an important role in regulating analgesia, appetite, obesity, learning and memory, synaptic plasticity, substance abuse disorders, and neuro-protection [1, 3–5]. TheCB 2 receptor, in contrast is found primarily in peripheral tissue, including tissue associated with immune system like spleen and tonsils, and is involved in cannabinoid mediated immune response[1,2]. Cannabinoid receptors bind and are activated by the lipid derived endocannabinoid ligands, anandamide and 2-arachidonoylglycerol[3,4].…”

“…The CB 1 receptor signals mainly through the activation of G proteins of Gi/o family, and regulates Gi/o-mediated inhibition of adenylyl cyclase, inhibition of Ca2+ channels, interaction with receptor tyrosine kinases and non-receptor Src kinases to activate the Extracellular Signal-Regulated Kinase (ERK1/2), and other cellular signaling via interactions with Gi/o proteins[1,2]. The CB 1 receptor also interacts with associated proteins that serve as regulators of cellular signaling (FAN, β-arrestins) or receptor trafficking (β-arrestins, SGIP1, GASP) [6–8].…”

The Intricate Influence of the Placebo Effect on Medical Cannabis and Cannabinoids

“…In 1941, cannabis was removed from the USP and the National Formulary [10]. The revival of research on the medicinal properties of cannabis regained momentum after the discovery of the endocannabinoid system (ECS) in the 1990s [11][12][13][14][15], peaking in the current worldwide campaign to legalize this plant and its psychoactive constituents for medical purposes.…”