ROLES OF METABOTROPIC GLUTAMATE RECEPTORS IN GLIAL FUNCTION AND GLIAL-NEURONAL COMMUNICATION

The amino acid glutamate plays a key role in brain function, One of th e major roles of glutamate is to mediate fast excitatory neurotransmis sion via activation of ionotropic glutamate receptors (iGluRs), More r ecently, however, it has become clear that glutamate also serves a reg ulatory function through activation of receptors coupled to modulation of second messenger systems [metabotropic glutamate receptors (mGluRs )]. A body of evidence suggests that mGluRs regulate neuronal function through modulation of ion channels and enzymes to modulate cellular e xcitability and synaptic transmission, Interestingly, it has become cl ear that in addition to activation of neuronal receptors, glutamate ca n activate both iGluRs and mGluRs on glia. A growing body of evidence suggests that the mGluRs on glia play important roles in both glial fu nction and mediation of intercellular signaling. (C) 1996 Wiley-Liss, Inc.