Elsevier

Neuroscience

Volume 6, Issue 12, December 1981, Pages 2657-2659, 2661-2668
Neuroscience

Involvement of the thalamus in the reciprocal regulation of the two nigrostriatal dopaminergic pathways

https://doi.org/10.1016/0306-4522(81)90110-XGet rights and content

Abstract

The effects of various sagittal sections on the asymmetric changes in [3H]dopamine release from nerve terminals and dendrites of the two nigrostriatal dopaminergic pathways induced by the application of α-methylparatyrosine ord-amphetamine in the left substantia nigra were examined in halothane-anaesthetized cats implanted with push-pull cannulae in both caudate nuclei and both substantiae nigrae. [3H]tyrosine was continuously delivered to each push-pull cannula and [3H]dopamine was estimated in serial fractions of superfusates. In cats without a lesion, α-methylparatyrosine (10−4M) reduced the release of [3H]dopamine in the left substantia nigra and induced an opposite effect in the left caudate nucleus. In contrast, [3H]dopamine release was enhanced in the right substantia nigra and reduced in the right caudate nucleus. Opposite asymmetric responses were observed in the four structures during application ofd-amphetamine (10−6M) into the left substantia nigra. The sagittal section of the mesencephalic decussations was without effect on the changes in [3H]dopamine release induced either by α-methylparatyrosine ord-amphetamine. The section of the corpus callosum and of the commissura anterior potentiated, whereas the section of the thalamic massa intermedia prevented thed-amphetamine-induced reduction of [3H]dopamine release in the left caudate nucleus. This could indicate that neuronal circuits under the control of contralateral structures may contribute to the regulation of the activity of ipsilateral dopaminergic neurons. Only the section of the thalamic massa intermedia prevented the contralateral responses evoked by the unilateral nigral application of α-methylparatyrosine ord-amphetamine.

These results suggest that nigrothalamic neurons and thalamic nuclei are involved in the reciprocal regulation of both nigrostriatal dopaminergic pathways.

Reference (36)

  • LevineM.S. et al.

    The spontaneous firing patterns of forebrain neurons—III. Prevention of induced asymmetries in caudate neuronal firing rates by unilateral thalamic lesions

    Brain Res.

    (1977)
  • NieoullonA. et al.

    Release of dopamine in both caudate nuclei and both substantiae nigrae in response to unilateral stimulation of cerebellar nuclei in the cat

    Brain Res.

    (1978,[object Object])
  • NieoullonA. et al.

    Release of dopamine evoked by electrical stimulation of the motor and visual areas of the cerebral cortex in both caudate nuclei and in the substantia nigra in the cat

    Brain Res.

    (1978,[object Object])
  • RoyceG.J.

    Cells of origin of subcortical afférents to the caudate nucleus: a horseradish peroxydase study in the cat

    Brain Res.

    (1978)
  • ScheibelM.E. et al.

    The organization of the ventral anterior nucleus of the thalamus. A Golgi study

    Brain Res.

    (1966)
  • AfifiA.K. et al.

    The cortico-nigral fibre tract. An expérimental Fink-Heimer study in cats

    J. Anat.

    (1974)
  • Albe-FessardD. et al.

    Cortical projections of cat medial thalamic cells

    Int. J. Neurosci.

    (1971)
  • BavaA. et al.

    Transcommissural interactions between specific thalamic nuclei relaying cerebello-cortical flow

    Archiv. Fisiol. Firenze

    (1972)
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