Characterization of a New Positive Allosteric Modulator of AMPA Receptors - PAM-43: Specific Binding of the Ligand and its Ability to Potentiate AMPAR Currents

Tatiana V Vyunova; Lioudmila A Andreeva; Konstantin V Shevchenko; Vladimir V Grigoriev; Vladimir A Palyulin; Mstislav I Lavrov; Ekaterina V Bondarenko; Elena E Kalashnikova; Nikolay F Myasoedov

doi:10.2174/1874467213666200303140834

Characterization of a New Positive Allosteric Modulator of AMPA Receptors - PAM-43: Specific Binding of the Ligand and its Ability to Potentiate AMPAR Currents

Curr Mol Pharmacol. 2020;13(3):216-223. doi: 10.2174/1874467213666200303140834.

Affiliations

¹ Sector of Regulatory Peptides, Department of Chemistry of Physiologically Active Substances, Institute of Molecular Genetics of the Russian Academy of Sciences, Moscow, Russia
² Institute of Physiologically Active Compounds of the Russian Academy of Sciences, Chernogolovka, Moscow Region, Russia
³ Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia
⁴ “Cyclomemorin” LTD, Kaluga Region, Obninsk, Russia
⁵ The Mental Health Research Center of the Russian Academy of Sciences, Moscow, Russia

PMID: 32124706
DOI: 10.2174/1874467213666200303140834

Abstract

Background: Currently, the most dynamic areas in the glutamate receptor system neurobiology are the identification and development of positive allosteric modulators (PAMs) of glutamate ionotropic receptors. PAM-based drugs are of great interest as promising candidates for the treatment of neurological diseases, such as epilepsy, Alzheimer's disease, schizophrenia, etc. Understanding the molecular mechanisms underlying the biological action of natural and synthetic PAMs is a key point for modifying the original chemical compounds as well as for new drug design.

Objective: We are trying to elaborate a system of molecular functional screening of ionotropic glutamate receptor probable PAMs.

Methods: The system will be based on the radioligand - receptor method of analysis and will allow rapid quantification of new AMPAR probable PAMs molecular activity. We plan to use a tritiumlabeled analogue of recently elaborated ionotropic GluR probable PAM ([3H]PAM-43) as the main radioligand.

Results: Here, we characterized the specific binding of the ligand and its ability to potentiate ionotropic GluR currents. The existence of at least two different sites of [3H]PAM-43 specific binding has been shown. One of the above sites is glutamate-dependent and is characterized by higher affinity. "Patchclamp" technique showed the ability of PAM-43 to potentiate ionotropic GluR currents in rat cerebellar Purkinje neurons in a concentration-dependent manner.

Conclusion: The possibility of using PAM-43 as a model compound to study different allosteric effects of potential regulatory drugs (AMPAR allosteric regulators) was shown. [3H]PAM-43 based screening system will allow rapid selection of new AMPAR probable PAM structures and quantification of their molecular activity.

Keywords: AMPA; AMPAR currents; Glutamate receptor; NMDA; [3H]PAM; allosteric modulation; positive allosteric modulator (PAM); radioligand.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Action Potentials / drug effects
Allosteric Regulation
Allosteric Site
Animals
Animals, Outbred Strains
Binding Sites
Excitatory Amino Acid Agonists / chemistry
Excitatory Amino Acid Agonists / pharmacology*
Humans
Ligands
Male
Molecular Structure
Patch-Clamp Techniques
Purkinje Cells / drug effects*
Purkinje Cells / physiology
Radioligand Assay
Rats
Receptors, AMPA / agonists*

Substances

Excitatory Amino Acid Agonists
Ligands
Receptors, AMPA