CB1 receptors can be found throughout the central and peripheral nervous system and have a range of effects on neurotransmitter release. They are part of the G-protein coupled receptor (GCPR) superfamily of heptihelical receptors and are one of the most abundant GPCR in the brain. This pathway illustrates a generic agonist binding to and activating a CB1 receptor. The resulting signaling pathway highlights cAMP signaling, which acts primarily through the inhibition of adenylyl cyclase to reduce protein kinase activity. This reduction influences current flow at voltage-dependent potassium channels, promoting the influx of ions into the presynaptic neuron. It also induces tyrosine phosphorylation of both FAK and FRNK (a distinct isoform of FAK). Activation of the receptor also inhibits calcium channels, reducing the flow of ions into the neuron. The combination of increased calcium and potassium within the synaptic cleft inhibits the proper polarization of the postsynaptic neuron, interrupting synaptic signalling. This leads to an analgesic effect, effectively preventing the propagation of pain signals. The activation of the CB1 receptor also activates MAPK, a serine kinase that is an essential part of the MAP signal transduction pathway. The MAPK signalling cascade is responsible for mediating a number of different cellular functions including adhesion and cell growth, which it achieves through regulating transcription and transcription. The effects of CB1 activation are broad, and the illustrated pathway serves as a general picture of its immediate cellular effects.

CB1 Receptor References