Experimental Brain Research

, Volume 142, Issue 2, pp 208–220

Stereological evaluation of neurons and glia in the monkey dorsal lateral geniculate nucleus following an early cerebral hemispherectomy

Authors

  • Denis Boire
    • School of Optometry, University of Montreal, CP 6128, Montreal, PQ, Canada, H3C 3J7
  • Hugo Théoret
    • Department of Psychology, University of Montreal, CP 6128, Montreal, PQ, Canada, H3C 3J7
  • Maurice Ptito
    • School of Optometry, University of Montreal, CP 6128, Montreal, PQ, Canada, H3C 3J7
Research Article

DOI: 10.1007/s00221-001-0921-8

Cite this article as:
Boire, D., Théoret, H. & Ptito, M. Exp Brain Res (2002) 142: 208. doi:10.1007/s00221-001-0921-8

Abstract.

The effects of an early, unilateral cerebral hemispherectomy on the cytoarchitecture of the dorsal lateral geniculate nucleus (dLGN) were quantitatively evaluated in the green monkey. The dLGN ipsilateral to the lesion showed a 73% reduction in size, more than 99% neuronal cell loss, 50% increase in glial cell density, but a 50% reduction in the total number of glial cells. The total number of neural and glial cells estimated for the dLGN contralateral to the ablation did not differ from control values. Despite evidence for substantial degeneration of the ipsilateral dLGN, cytochrome oxidase histochemistry revealed a small population of surviving cells that exhibited features of neuronal cells. More surviving cells were found in the parvocellular than in the magnocellular layers, and surviving parvocellular cells had the same size-frequency distribution as Nissl-stained neurons in an intact animal. These findings suggest that the intrinsic geniculate circuitry may be able to sustain the residual interneurons that can, in turn, contribute to maintaining retinal and brainstem afferents. The remaining neurons in the dLGN following hemispherectomy appear to be insufficient in number to be importantly implicated in the residual visual functions that have been reported in some hemispherectomized patients.

Visual cortex lesion Cell death Gliosis Optical disector Cercopithecus aethiops

Copyright information

© Springer-Verlag 2001