Glutamate-induced transient modification of the postsynaptic density

Academic Article

Abstract

  • Depolarization of rat hippocampal neurons with a high concentration of external potassium induces a thickening of postsynaptic densities (PSDs) within 1.5-3 min. After high-potassium treatment, PSDs thicken 2.1-fold in cultured neurons and 1.4-fold in hippocampal slices compared with their respective controls. Thin-section immunoelectron microscopy of hippocampal cultures indicates that at least part of the observed thickening of PSDs can be accounted for by an accumulation of Ca2+/calmodulin-dependent protein kinase II (CaMKII) on their cytoplasmic faces. Indeed, PSD-associated gold label for CaMKII increases 5-fold after depolarization with potassium. The effects of high-potassium treatment on the composition and structure of the PSDs are mimicked by direct application of glutamate. In cultures, glutamate-induced thickening of PSDs and the accumulation of CaMKII on PSDs are reversed within 5 min of removal of glutamate and Ca2+ from the extracellular medium. These results suggest that PSDs are dynamic structures whose thickness and composition are subject to rapid and transient changes during synaptic activity.
  • Digital Object Identifier (doi)

    Pubmed Id

  • 25245126
  • Author List

  • Dosemeci A; Tao-Cheng JH; Vinade L; Winters CA; Pozzo-Miller L; Reese TS
  • Start Page

  • 10428
  • End Page

  • 10432
  • Volume

  • 98
  • Issue

  • 18