Current Topics in Medicinal Chemistry - Volume 5, Issue 9, 2005

Glutamate (glutamic acid) is the major excitatory neurotransmitter in the mammalian CNS, exterting its modulatory effects through either ionotropic or metabotropic glutamate receptors (mGluRs). The mGluRs are family C G-protein coupled receptors, characterized by a large extracellular amino-terminal agonist binding site. Eight mGluRs have been cloned, sequenced and assigned to three groups based on th Read More

This review provides an overview of the drug discovery process used to identify, develop and characterize the first positive allosteric modulators of the metabotropic glutamate receptor (mGluR) subtype 5 (mGluR5). Discovery and optimization of three series of positive allosteric modulators are described, each using different approaches. The symmetric benzaldazine series was discovered and optimized from samples already exi Read More

Our understanding of glutamatergic transmission in the central nervous system has been greatly expanded with the discovery and investigation of the metabotropic glutamate receptor family. Complementing the ionotropic glutamategated ion channels, these G-protein coupled receptors play critical roles in neuronal and glial functions such as the modulation of neuronal excitability, synaptic transmission, and various metabolic Read More

This article describes recent advances in the development of subtype-selective, noncompetitive modulators of metabotropic glutamate receptor subtype 1 (mGluR1). mGluR1 plays an important role in modulating synaptic transmission and neuronal excitability via intracellular signal transduction pathways and has been implicated in a number of CNS disorders. Allosteric modulation of mGluR1 by potentiation and anta Read More

This article describes recent medicinal chemistry progress toward selective potentiators of the metabotropic glutamate receptor 2 (mGluR2). Groups at Lilly and Merck have identified new classes of potentiators that exhibit selectivity for mGluR2 over the seven other subtypes of mGluRs. Structure-activity relationships as well as pharmacokinetic properties and in vivo activity are reviewed.

Over the last several years a great deal of interest has been focused on the metabotropic glutamate receptors as potential targets for the treatment of a variety of disorders of the central nervous system. Recently, selective agonist or allosteric potentiators of mGluR4, one of the group III mGluRs, have been proposed as potential novel therapeutics for the palliative treatment of Parkinson's disease and some forms of epi Read More

Extensive research into the functions of glutamate and glutamate receptors in the central nervous system (CNS) has shown an essential role of metabotropic glutamate (mGlu) receptors in normal brain functions, but also in neurological and psychiatric disorders. The precise functions of these receptors remain undefined, and progress toward understanding their functions has been hampered by the lack of selective ligan Read More

Metabotropic glutamate receptors (mGluRs) have been implicated in a variety of neurological and psychiatric disorders. This article describes recent progress in the development of agonists and antagonists for mGluR 6, 7, and 8. All of them are conformationally constrained or substituted amino acids, and they act at N-terminal extracellular glutamate binding site. These ligands serve as valuable tools for studying physiolog Read More