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


CONCLUSIONS
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.
Poveda
A
A
University of Fribourg, Department of Medicine, Unit of Anatomy, Rte. Albert Gockel 1, 1700 Fribourg, Switzerland. apoveda-ramos@nki.rfmh.org
Kretz
R
R
D000221:Adaptation, Ocular / Q000502:physiology / Q000528:radiation effects; D000818:Animals; D001921:Brain / Q000166:cytology / Q000378:metabolism*; D001931:Brain Mapping; D003623:Dark Adaptation / Q000502:physiology / Q000528:radiation effects; D005260:Female; D005829:Geniculate Bodies / Q000166:cytology / Q000378:metabolism; D007150:Immunohistochemistry; D008027:Light; D008297:Male; D010775:Photic Stimulation; D016760:Proto-Oncogene Proteins c-fos / Q000032:analysis / Q000378:metabolism*; D020649:Pulvinar / Q000166:cytology / Q000378:metabolism; D012160:Retina / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects; D012165:Retinal Ganglion Cells / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects; D013045:Species Specificity; D013477:Superior Colliculi / Q000166:cytology / Q000378:metabolism; D014417:Tupaia / Q000033:anatomy & histology / Q000378:metabolism*; D014793:Visual Cortex / Q000166:cytology / Q000378:metabolism; D014795:Visual Pathways / Q000166:cytology / Q000378:metabolism*; D014796:Visual Perception / Q000502:physiology* / Q000528:radiation effects
D016760:Proto-Oncogene Proteins c-fos