PMID: 21543522

Authors:

Timm DM, Benveniste M, Weeks AM, Nisenbaum ES, Partin KM

Title:

Structural and Functional Analysis of Two New Positive Allosteric Modulators of GluA2 Desensitization and Deactivation.

Journal:

Mol Pharmacol. 2011 May 4.

Abstract:

At the dimer interface of the extracellular ligand-binding domain of AMPA receptors a hydrophilic pocket is formed that is known to interact with two classes of positive allosteric modulators, represented by cyclothiazide and the ampakine CX614. Here we present structural and functional data on two new positive allosteric modulators of AMPA receptors, CMPDA and CMPDB. Crystallographic data show that these compounds bind within the modulator-binding pocket, and that substituents of each compound overlap with distinct moieties of cyclothiazide and CX614. The goals of the present study were to determine 1) the degree of modulation by CMPDA and CMPDB of AMPA receptor deactivation and desensitization; 2) whether these compounds are splice isoform-selective; and, 3) whether predictions of mechanism of action could be inferred by comparing molecular interactions between the ligand binding domain and each compound to those of cyclothiazide and CX614. CMPDB was found to be more isoform-selective than would be predicted from initial binding assays. Importantly, these new compounds are both more potent and more efficacious, and also may be more clinically relevant, than the previously described AMPA receptor modulators.