Acute dissociation for analyses of NMDA receptor function in cortical neurons during aging.

TitleAcute dissociation for analyses of NMDA receptor function in cortical neurons during aging.
Publication TypeJournal Article
Year of Publication2003
AuthorsKuehl-Kovarik CM, Partin KM, Magnusson KR
JournalJournal of neuroscience methods
Volume129
Issue1
Pagination11-7
Date Published2003 Oct 15
ISSN0165-0270
KeywordsAging, Animals, Calcium, Cells, Cultured, Cerebral Cortex, Dose-Response Relationship, Drug, Excitatory Amino Acid Agonists, Excitatory Amino Acid Antagonists, Male, Membrane Potentials, Mice, Mice, Inbred C57BL, N-Methylaspartate, Neurons, Patch-Clamp Techniques, Piperidines, Receptors, N-Methyl-D-Aspartate, Time Factors
Abstract

The present study was designed to determine if functional age differences in the NMDA epsilon2 (NR2B) subunit were detectable at the level of individual cortical neurons. Neurons were acutely dissociated from the frontal and prefrontal cortices of young adult, middle-aged, or old mice, using a combination of proteinase K and trypsin followed by manual trituration. After overnight culture, patch-clamp electrophysiology and rapid perfusion were used to obtain whole-cell responses to 300 microM NMDA, with or without the potent NR2B antagonist ifenprodil. Healthy, phase-bright cortical neurons were isolated from animals of all ages. Cell diameter and capacitance was consistent between ages. We were able to perform kinetic analyses of the NMDA-evoked response, and demonstrated a significant increase in the rate of deactivation with increasing age. In addition, we observed a significant effect of high-concentration ifenprodil on the NMDA-evoked response in old animals. Thus, this method is ideal for the dissociation of neurons from the brain of both young and old animals, and offers a powerful tool for functional analysis at the level of the individual cell.

Alternate JournalJ. Neurosci. Methods