Functional diversity of GABA-activated Cl- currents in Purkinje versus granule neurons in rat cerebellar slices

Neuron. 1994 Jan;12(1):117-26. doi: 10.1016/0896-6273(94)90157-0.

Abstract

In rat cerebellar slices, we compared whole-cell recordings of spontaneous inhibitory postsynaptic currents (sIPSCs) with Cl- currents resulting from pulses of GABA (1 mM, < 2 ms) to outside-out patches from Purkinje and granule neurons. sIPSCs in Purkinje cells decayed with a single fast exponential, as previously reported, whereas in granule cells sIPSC decay was best described by the sum of a fast and a slow exponential curve, with a variable contribution of the slow component to the peak current. GABA pulses to nucleated patches from granule cells elicited Cl- currents with decays similar to sIPSC decays, whereas in patches from Purkinje neurons GABA pulses produced Cl- currents decaying largely with a fast component, but often followed by a slower exponential. GABA concentration steps produced rapidly desensitizing currents in patches from both cerebellar neurons. In distinct cerebellar neurons, specific functional properties of GABAA receptors may relate to the presence of distinct receptor subtypes.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cerebellum / cytology
  • Cerebellum / physiology*
  • Chloride Channels / drug effects
  • Chloride Channels / physiology*
  • In Vitro Techniques
  • Kinetics
  • Neurons / drug effects
  • Neurons / physiology*
  • Purkinje Cells / drug effects
  • Purkinje Cells / physiology*
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, GABA-A / drug effects
  • Receptors, GABA-A / physiology*
  • Synapses / drug effects
  • Synapses / physiology*
  • Synaptic Transmission / drug effects
  • Synaptic Transmission / physiology
  • gamma-Aminobutyric Acid / pharmacology*

Substances

  • Chloride Channels
  • Receptors, GABA-A
  • gamma-Aminobutyric Acid