mGluR, or metabotropic glutamate receptor, is a type of glutamate receptor that operates through an indirect metabotropic process. As a member of the group C family of G-protein-coupled receptors, or GPCRs, mGluRs bind with glutamate, an amino acid functioning as an excitatory neurotransmitter. These receptors perform a range of functions in both the central and peripheral nervous systems, including learning, memory, anxiety, and the perception of pain. mGluRs are present in both pre- and postsynaptic neurons within synapses of the hippocampus, cerebellum, and cerebral cortex, as well as other parts of the brain and in peripheral tissues. The eight different types of mGluRs, mGluR1 to mGluR8, plus the two subclasses of mGluR-1 (a and b), are categorized into groups I, II, and III based on their receptor structure and physiological activity. mGluR-4 activators offered by Santa Cruz Biotechnology activate mGluR-4 and, in some cases, other G-protein-coupled receptors (GPCRs).