Cannabinoid- and lysophosphatidylinositol-sensitive receptor GPR55 boosts neurotransmitter release at central synapses.

ABSTRACT: G protein-coupled receptor (GPR) 55 is sensitive to certain cannabinoids, it is expressed in the brain and, in cell cultures, it triggers mobilization of intracellular Ca(2+). However, the adaptive neurobiological significance of GPR55 remains unknown. Here, we use acute hippocampal slices and combine two-photon excitation Ca(2+) imaging in presynaptic axonal boutons with optical quantal analysis in postsynaptic dendritic spines to find that GPR55 activation transiently increases release probability at individual CA3-CA1 synapses. The underlying mechanism involves Ca(2+) release from presynaptic Ca(2+) stores, whereas postsynaptic stores (activated by spot-uncaging of inositol 1,4,5-trisphosphate) remain unaffected by GPR55 agonists. These effects are abolished by genetic deletion of GPR55

SUBMITTER: Sylantyev S 

PROVIDER: S-EPMC3612675 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature