c-Fos expression in the visual system of the tree shrew (Tupaia belangeri)

J Chem Neuroanat. 2009 Jul;37(4):214-28. doi: 10.1016/j.jchemneu.2009.03.006. Epub 2009 Apr 2.


c-Fos is a nuclear phosphoprotein coded by the proto-oncogen c-fos which can be detected immunohistochemically after both physiological and pathological stimuli. This property is of great importance, because it offers a valuable tool for morphofunctional identification of activated neurons. We have studied the neuronal activity in the visual pathway of Tupaia belangeri within the following anatomical structures: retina, superior colliculus (SC), dorsal lateral geniculate nucleus (dLGN), pulvinar (Pu), parabigeminal (PBG) nucleus and primary visual cortex (V1) analyzing the c-Fos expression after exposing the tree shrews to different light stimuli (white light -control positive group-, green light, blue light and darkness conditions -control negative group-). Our findings suggest that in the retina, the ganglion cells and the cells of the inner nuclear layer respond better to blue and green light stimuli, when comparing the c-Fos expression between white, green, blue lights and darkness conditions. However, in the SC, dLGN, Pu, PBG nucleus and V1 another pattern of c-Fos expression is observed: a maximum expression for the control positive group, a minimum expression for the control negative group and intermediate expressions within the blue and green light groups.

Conclusion: the expression levels of c-Fos protein are able to show significant differences between distinct light stimuli in all anatomical structures studied (retina, SC, dLGN, Pu, PBG and V1) of T. belangeri.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Ocular / physiology
  • Adaptation, Ocular / radiation effects
  • Animals
  • Brain / cytology
  • Brain / metabolism*
  • Brain Mapping
  • Dark Adaptation / physiology
  • Dark Adaptation / radiation effects
  • Female
  • Geniculate Bodies / cytology
  • Geniculate Bodies / metabolism
  • Immunohistochemistry
  • Light
  • Male
  • Photic Stimulation
  • Proto-Oncogene Proteins c-fos / analysis
  • Proto-Oncogene Proteins c-fos / metabolism*
  • Pulvinar / cytology
  • Pulvinar / metabolism
  • Retina / cytology
  • Retina / metabolism
  • Retina / radiation effects
  • Retinal Ganglion Cells / cytology
  • Retinal Ganglion Cells / metabolism
  • Retinal Ganglion Cells / radiation effects
  • Species Specificity
  • Superior Colliculi / cytology
  • Superior Colliculi / metabolism
  • Tupaia / anatomy & histology
  • Tupaia / metabolism*
  • Visual Cortex / cytology
  • Visual Cortex / metabolism
  • Visual Pathways / cytology
  • Visual Pathways / metabolism*
  • Visual Perception / physiology*
  • Visual Perception / radiation effects


  • Proto-Oncogene Proteins c-fos