Zolpidem modulates GABA(A) receptor function in subthalamic nucleus

Neurosci Res. 2007 May;58(1):77-85. doi: 10.1016/j.neures.2007.02.002. Epub 2007 Feb 9.

Abstract

The subthalamic nucleus occupies a position in the indirect pathway of basal ganglia circuit, which plays an important role in the movement regulation. Zolpidem is an imidazopyridine agonist with a high affinity on the benzodiazepine site of GABA(A) receptors containing alpha 1 subunit. Recently, zolpidem has been reported to be useful in treating subgroups of parkinsonian patients. A high density of zolpidem binding sites has been shown in rat subthalamic nucleus. To further investigate the modulation of zolpidem on GABA(A) receptor-mediated inhibitory synaptic current in subthalamic nucleus, whole-cell patch clamp recordings were used in the present study. Zolpidem at 100nM significantly prolonged the decay time and rise time of miniature inhibitory postsynaptic currents, with no effect on the amplitude and frequency. The benzodiazepine antagonist flumazenil could completely block the potentiation induced by zolpidem, confirming the specificity on the benzodiazepine site. At a high concentration of 1 microM, zolpidem significantly increased the decay time, rise time, amplitude and frequency of miniature inhibitory postsynaptic currents. In the behaving rats, unilateral microinjection of zolpidem into subthalamic nucleus induced a significant contralateral rotation. The present findings on the effect of zolpidem in subthalamic nucleus provide a rationale for further investigations into its potential in the treatment of Parkinson's disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Flumazenil / pharmacology
  • GABA Agonists / pharmacology
  • GABA Modulators / pharmacology
  • GABA-A Receptor Agonists
  • GABA-A Receptor Antagonists
  • Motor Activity / drug effects
  • Motor Activity / physiology
  • Neural Inhibition / drug effects*
  • Neural Inhibition / physiology
  • Neural Pathways / drug effects*
  • Neural Pathways / metabolism
  • Neurons / drug effects*
  • Neurons / metabolism
  • Organ Culture Techniques
  • Parkinson Disease / drug therapy
  • Parkinson Disease / metabolism
  • Parkinson Disease / physiopathology
  • Patch-Clamp Techniques
  • Pyridines / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Reaction Time / drug effects
  • Reaction Time / physiology
  • Receptors, GABA-A / drug effects*
  • Receptors, GABA-A / metabolism
  • Subthalamic Nucleus / drug effects*
  • Subthalamic Nucleus / metabolism
  • Synaptic Transmission / drug effects
  • Synaptic Transmission / physiology
  • Time Factors
  • Zolpidem
  • gamma-Aminobutyric Acid / metabolism

Substances

  • GABA Agonists
  • GABA Modulators
  • GABA-A Receptor Agonists
  • GABA-A Receptor Antagonists
  • Pyridines
  • Receptors, GABA-A
  • Flumazenil
  • gamma-Aminobutyric Acid
  • Zolpidem