Increased subthalamic neuronal activity after nigral dopaminergic lesion independent of disinhibition via the globus pallidus

Neuroscience. 1996 May;72(1):105-15. doi: 10.1016/0306-4522(95)00535-8.


Electrophysiological records of unit activity were used to compare the effects of excitotoxic pallidal lesions and 6-hydroxydopamine-induced damage to the midbrain dopaminergic neurons on the discharge rates and patterns of the subthalamic neurons. Removal of the pallidal input induced a slight, but statistically significant, increase (19.5%) in the discharge rate and no change in the firing pattern when compared to control animals. The rats with a dopaminergic lesion showed greater increase (105.7%) while the firing pattern activity of the subthalamic neurons became more irregular, with burst. These results indicate that the increased activity of the subthalamic neurons following a midbrain dopaminergic lesion cannot be due solely to inhibition-disinhibition involving the striato-pallido-subthalamic pathway and induced by the striatal dopaminergic depletion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dopamine / physiology*
  • Excitatory Amino Acid Agonists / administration & dosage
  • Excitatory Amino Acid Agonists / toxicity
  • Extracellular Space / drug effects
  • Extracellular Space / metabolism
  • Globus Pallidus / physiology*
  • Ibotenic Acid / administration & dosage
  • Ibotenic Acid / toxicity
  • Male
  • Microinjections
  • Neurons / physiology*
  • Oxidopamine / administration & dosage
  • Oxidopamine / toxicity
  • Rats
  • Rats, Sprague-Dawley
  • Substantia Nigra / physiology*
  • Sympatholytics / administration & dosage
  • Sympatholytics / toxicity
  • Thalamic Nuclei / cytology
  • Thalamic Nuclei / physiology*


  • Excitatory Amino Acid Agonists
  • Sympatholytics
  • Ibotenic Acid
  • Oxidopamine
  • Dopamine