Zinc and zolpidem modulate mIPSCs in rat neocortical pyramidal neurons

Academic Article

Abstract

  • Pharmacological modulation of γ-aminobutyric acid-A (GABA(A)) receptors can provide important information on the types of subunits composing these receptors. In recombinant studies, zinc more potently inhibits αβ subunits compared with the αβγ combination, whereas modulation by nanomolar concentrations of the benzodiazepine type 1-selective agonist zolpidem is conferred by the α1βγ2 subunit combination. We examined four properties of miniature inhibitory postsynaptic currents (mIPSCs) from identified necortical pyramidal cells in rat brain slices: decay time constant, peak amplitude, rate of rise, and interevent interval. Exposure to 50 μM zinc reduced the decay time constant, peak amplitude, and rate of rise with no effect on interevent interval. Zolpidem enhanced mIPSCs in a concentration- dependent manner. Both 20 and 100 nM zolpidem increased the decay time constants of mIPSCs. In some cells, both peak amplitude and rate of rise were also enhanced. All cells treated with zinc were also responsive to zolpidem. These results show that neocortical pyramidal cells have a population of GABA(A) receptors sensitive to both zinc and zolpidem.
  • Authors

    Digital Object Identifier (doi)

    Author List

  • DeFazio T; Hablitz JJ
  • Start Page

  • 1670
  • End Page

  • 1677
  • Volume

  • 80
  • Issue

  • 4