Group I mGluR receptors as mediators of learning and memory

Group I metabotropic glutamate receptors (mGluR1 and mGluR5) are predominantly expressed on postsynaptic elements and are intricately involved in various forms of neural plasticity, including long-term potentiation (LTP) and long-term depression (LTD). Given the well-established role of these and other forms of neural plasticity in learning and memory, it comes as no surprise that pharmacological or genetic deletion of Group I metabotropic glutamate receptors (mGluR1 and mGluR5) have deleterious effects on learning and memory in numerous behavioral paradigms. In contrast, positive allosteric modulation of these receptors, especially mGluR5, can enhance synaptic plasticity and improve various aspects of cognition, including spatial learning, behavioral flexibility, and the extinction of fear-related and drug-seeking behaviors. In this chapter we review the current literature regarding the role of Group I mGluR receptors in synaptic plasticity, learning and memory.