C-fos and c-jun expressions in nitric oxide synthase immunoreactive neurons in the lateral geniculate nucleus of experimental glaucomatous rats.
The present study was initiated to investigate the expressions of c-fos and c-jun in nitric oxide synthase immunoreactive neurons and their possible roles in the lateral geniculate nucleus (LGN) of glaucomatous rats. An experimental one-eye glaucoma model was created by cauterisation of the limbal-derived veins. Animals were killed by cardiac perfusion, and brains containing the LGN were removed and processed for c-fos, c-jun and neuronal nitric oxide synthase (nNOS) immunohistochemistry. No c-fos or c-jun immunoreactivity was observed in the LGN of control rats. In the glaucomatous rats, expression of c-fos and c-jun was induced bilaterally in the ventral LGN (vLGN) as early as 2 h postoperation. The number of c-fos-immunopositive cells increased at 1 and 2 days postoperation in both the lateral and medial subdivisions of the vLGN (vLGN-l and vLGN-m). Thereafter, the expression decreased and was totally absent at 1 and 2 weeks. No c-fos was induced in the dorsal LGN (dLGN). C-jun-immunopositive cells were mainly localised in the intergeniculate leaflet and vLGN. Few neurons were observed in the dLGN. The number of c-jun-immunopositive cells decreased at 1 and 2 weeks postoperation. Some of the c-fos- and c-jun-immunopositive cells were also nNOS immunopositive. The present results reveal that glaucoma activates the expressions of immediate early genes (IEGs) in some cells of the LGN. It is postulated that they may play important roles in the pathologic processes of glaucoma. The relationship between these IEGs and nitric oxide was also discussed.
Wang
Xu
X
Department of Anatomy, Faculty of Medicine, National University of Singapore, MD10, 4 Medical Drive, 10 Kent Ridge Crescent, Singapore 117597.
Tay
Samuel Sam-Wah
SS
Ng
Yee-Kong
YK
D000818:Animals; D002452:Cell Count; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D005829:Geniculate Bodies / Q000201:enzymology* / Q000473:pathology / Q000503:physiopathology; D005901:Glaucoma / Q000201:enzymology* / Q000473:pathology / Q000503:physiopathology; D007150:Immunohistochemistry; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D009410:Nerve Degeneration / Q000201:enzymology / Q000473:pathology / Q000503:physiopathology; D009474:Neurons / Q000378:metabolism* / Q000473:pathology; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012165:Retinal Ganglion Cells / Q000473:pathology*; D014795:Visual Pathways / Q000473:pathology / Q000503:physiopathology*
D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase