Identifying NMDA receptor subtypes in the ventral respiratory column (847.6)

Abstract

The ventral respiratory column (VRC) is a region in the brainstem shown to control breathing patterns in mammals. Using a mouse model, cells from this region are dissociated, plated and incubated with a dye that indicates changes in cytoplasmic calcium levels. Hundreds of cells are monitored as a diverse set of pharmacological agents are applied. The spectrum of cellular responses provides a profile of the receptors found on each of these neurons. Previously, varieties of cell classes were shown to contain NMDA receptors. However, specific compositions of subunits within these receptors are not known. These receptors are ligand gated ion channels composed of four non‐covalently bound protein subunits. Each subunit has a different response profile determined by interactions of agonist and antagonists. Conantokins (peptides isolated from snail venom) and other compounds afford understanding which NMDA receptor subtypes are present in different cell‐classes. This project has continued to classify the subunit compositions of NMDA receptors with the ultimate goal of defining which NMDA receptor subunits are present in each class. The results indicate that different neuronal subclasses express different NMDA response subtypes. This will provide valuable information on the individual neurons in the networks of the VRC, and will allow for pharmacological interventions to change behavior in this region. Grant Funding Source: Supported by GM48677