Complex interactions between mGluRs, intracellular Ca2+ stores and ion channels in neurons

Metabotropic glutamate receptors (mGluRs) can increase intracellular Ca2+ c oncentration via Ins(1,4,5)P-3- and ryanodine-sensitive Ca2+ stores in neur ons. Both types of store are coupled functionally to Ca2+ permeable channel s found in the plasma membrane. The mGluR-mediated increase in intracellula r Ca2+ concentration can activate Ca2+-sensitive K+ channels and Ca2+ depen dent nonselective cationic channels. These mGluR-mediated effects often res ult from mobilization of Ca2+ from ryanodine-sensitive, rather than Ins(1,4 ,5)P-3-sensitive, Ca2+ stores, suggesting that close functional interaction s exist between mGluRs, intracellular Ca2+ stores and Ca2+-sensitive ion ch annels in the membrane.