Stereological evaluation of substantia nigra cell number in normal and hemispherectomized monkeys

doi:10.1016/S0006-8993(99)01598-X

Brain Research

Volume 835, Issue 2, 24 July 1999, Pages 354-359

https://doi.org/10.1016/S0006-8993(99)01598-X Get rights and content

Abstract

The assessment of the anatomical consequences of cortical lesions on subcortical visual relays is necessary to further understand residual visual capacities. Unbiased stereological techniques were used to evaluate cell numbers in the substantia nigra (SN), a structure involved in the control of saccadic eye movements. Cell numbers were very similar in the ipsi- and contralateral SN of the hemispherectomized animal (329,926 vs. 310,248). These numbers are close to what was observed in the normal monkey (300,130 and 320,859). In one case, part of the striatum was lesioned in addition to the cerebral hemisphere. Noticeable effects were observed in the SN ipsilateral to the cortical lesion: volume was reduced by 30.5% while the number of neurons, compared to the contralateral side, dropped by 43.2% (186,644 vs. 328,757). These results suggest that due to its anatomical sparing following hemispherectomy the SN, in addition to other subcortical structures, is in a prime position to modulate the spared saccadic behaviors seen after massive cortical injuries.

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Acknowledgements

This work was supported by grants from the National Science and Engineering Research Council of Canada (NSERC) and from FCAR (Québec).

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Short communicationStereological evaluation of substantia nigra cell number in normal and hemispherectomized monkeys

Abstract

Section snippets

Acknowledgements

Trends Neurosci.

Trends Neurosci.

Behav. Brain Res.

Brain Res.

Prog. Brain Res.

Am. J. Ophtal.

Prog. Brain Res.

Effects of aging on the size, density, and number of rhesus monkey lateral geniculate neurons

J. Comp. Neurol.

Investigations of the anatomical basis of blindsight: an fMRI study of hemispherectomized patients

Hum. Brain Map.

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J. Microsc.

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J. Microsc.

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Short communication
Stereological evaluation of substantia nigra cell number in normal and hemispherectomized monkeys