Dopamine and skilled limb use in the rat: more severe bilateral impairments follow substantia nigra than sensorimotor cortex 6-hydroxydopamine injection

Behav Brain Res. 1992 Mar 15;47(1):89-92. doi: 10.1016/s0166-4328(05)80255-4.

Abstract

The experiments examined the suggestion that the dopaminergic (DA) projection to the motor cortex are involved in the motor impairments that follow complete hemitelencephalic DA depletions. The neurotoxin, 6-hydroxydopamine (6-OHDA), was injected unilaterally into the sensorimotor cortex (MCtx), the ventral tegmental area (VTA), or into the substantia nigra pars compacta (SN) of rats trained to reach for food with either forelimb. The SN injections produced large (greater than 95%) unilateral striatal dopamine (DA) depletions and severe bilateral impairments in limb use. VTA and MCtx injections did not produce impairments in limb use or severe depletions of cortical DA. An effective test of the contribution of cortical DA to skilled limb use must await a more effective technique for producing selective cortical DA depletion. Nevertheless, the results suggest that the severe impairments of skilled forelimb use that follow hemitelencephalic DA depletions may stem primarily from depletion of the nigrostriatal DA projection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain Mapping
  • Dominance, Cerebral / drug effects
  • Dominance, Cerebral / physiology*
  • Dopamine / physiology*
  • Female
  • Motor Cortex / drug effects
  • Motor Cortex / physiology*
  • Motor Skills / drug effects
  • Motor Skills / physiology*
  • Oxidopamine / pharmacology
  • Psychomotor Performance / drug effects
  • Psychomotor Performance / physiology
  • Rats
  • Somatosensory Cortex / drug effects
  • Somatosensory Cortex / physiology*
  • Substantia Nigra / drug effects
  • Substantia Nigra / physiology*
  • Tegmentum Mesencephali / drug effects
  • Tegmentum Mesencephali / physiology

Substances

  • Oxidopamine
  • Dopamine