Oligodendrocyte precursor cell AMPA receptors differ with age and brain region while kainate receptors remain stable.

Oligodendrocyte precursor cells (OPCs) proliferate and differentiate into myelinating oligodendrocytes throughout life. Many cues modulate OPC proliferation and differentiation, including neuronal activity, which OPCs sense through voltage-gated ion channels and glutamate receptors. However, OPCs display regional and temporal diversity in the membrane surface expression of these channels and receptors, altering their capacity to sense and respond to neuronal activity. Here, we use whole-cell patch-clamp in acute brain slices and bath-apply 3 μM kainate or 10 μM AMPA to investigate the heterogeneity in kainate and AMPA receptor membrane surface expression. We find that, while kainate receptor current density remains stable with age, OPCs do not respond to neuronal kainate receptor-specific drugs. In contrast, AMPA receptor current density differs with age and between regions, likely due to altered Ca(2+) permeability and receptor desensitization. The temporal changes in AMPA-evoked currents in OPCs correlate with reported age-related changes in proliferation and differentiation potential.