Cannabinoid signalling.

Dirk G Demuth; Areles Molleman

doi:10.1016/j.lfs.2005.05.055

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PubMed · 16109430

Cannabinoid signalling.

Dirk G Demuth·Areles Molleman

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Abstract

After their discovery, the two known cannabinoid receptors, CB(1) and CB(2), have been the focus of research into the cellular signalling mechanisms of cannabinoids. The initial assessment, mainly derived from expression studies, was that cannabinoids, via G(i/o) proteins, negatively modulate cyclic AMP levels, and activate inward rectifying K(+) channels. Recent findings have complicated this assessment on different levels: (1) cannabinoids include a wide range of compounds with varying profiles of affinity and efficacy at the known CB receptors, and these profiles do not necessarily match their biological activity; (2) CB receptors appear to be intrinsically active and possibly coupled to more than one type of G protein; (3) CB receptor signalling mechanisms are diverse and dependent on the system studied; (4) cannabinoids have other targets than CB receptors. The aim of this mini review is to discuss the current literature regarding CB receptor signalling pathways. These include regulation of adenylyl cyclase, MAP kinase, intracellular Ca(2+), and ion channels. In addition, actions of cannabinoids that are not mediated by CB(1) or CB(2) receptors are discussed.

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Adenylyl Cyclases Animals Calcium Cannabinoids GTP-Binding Proteins Humans Ion Channels Mitogen-Activated Protein Kinases Receptor, Cannabinoid, CB1 Receptor, Cannabinoid, CB2 Receptors, N-Methyl-D-Aspartate Receptors, Opioid Receptors, Serotonin, 5-HT3 Signal Transduction TRPV Cation Channels Journal Article Review

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Dirk G Demuth, Areles Molleman. 2005-08-18. Cannabinoid signalling.. https://doi.org/10.1016/j.lfs.2005.05.055

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