Metabotropic glutamate second messengers

The metabotropic glutamate receptor family includes at least seven different types of G protein-coupled receptors (mGluRj 7). These are linked to different second messenger systems and lead to the increase of intracellular Ca or the decrease of cyclic AMP (cAMP). The increase of intracellular Ca leads to the phosphorylation of target proteins in the cell. 

As described in section 2.3, metabotropic receptors are divided into families, based upon second messenger mechanisms and functional effect. Group I receptors potentiate presynaptic glutamate release and NMDA receptor-mediated neurotransmission. Therapeutic effectiveness of group I agonists is therefore... 

There are two sub-types of glutamate receptors in glutamatergic structures in brain ionotropic and metabotropic ones, which differ in both localization (the former — predominantly on the postsynaptic membrane and the latter — on both post- and presynaptic membranes) and their functional role. Activation of ionotropic receptors provides electric activity of neurons (generation of action potential) whereas that of metabotropic receptors modifies metabolism of the neuronal cell and, in particular, conformational state and properties of ionotropic receptors this modifying effect is performed by second messengers which formation involves activation of subsequent G-proteins. 

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