|
|
||||||||
1 From the Kenneth C. Swan Ocular Neurobiology Laboratory, Casey Eye Institute, Oregon Health Sciences University; and the 2 Portland Veterans Affairs Hospital and Medical Center, Oregon.
PURPOSE. To determine the diurnal intraocular pressure (IOP) response of Brown Norway rat eyes after sclerosis of the aqueous humor outflow pathways and its relationship to optic nerve damage.
METHODS. Hypertonic saline was injected into a single episcleral vein in 17 animals and awake IOP measured in both the light and dark phases of the circadian cycle for 34 days. Mean IOP for light and dark phases during the experimental period were compared with the respective pressures of the uninjected fellow eyes. Optic nerve cross sections from each nerve were graded for injury by five independent masked observers.
RESULTS. For fellow eyes, mean light- and dark-phase IOP was 21 ± 1 and 31 ± 1 mm Hg, respectively. For four experimental eyes, mean IOPs for both phases were not altered. Six eyes demonstrated significant mean IOP elevations only during the dark phase. Of these, five showed persistent, large circadian oscillations, and four had partial optic nerve lesions. The remaining seven eyes experienced significant IOP elevations during both phases, and all had extensive optic nerve damage.
CONCLUSIONS. Episcleral vein injection of hypertonic saline is more likely to increase IOP during the dark phase than the light. This is consistent with aqueous outflow obstruction superimposed on a circadian rhythm of aqueous humor production. Because these periodic IOP elevations produced optic nerve lesions, both light- and dark-phase IOP determinations are necessary for accurate correlation of IOP history to optic nerve damage in animals housed in a lightdark environment.
This article has been cited by other articles:
![]() |
E. C. Johnson, L. Jia, W. O. Cepurna, T. A. Doser, and J. C. Morrison Global Changes in Optic Nerve Head Gene Expression after Exposure to Elevated Intraocular Pressure in a Rat Glaucoma Model Invest. Ophthalmol. Vis. Sci., July 1, 2007; 48(7): 3161 - 3177. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Bakalash, A. Rolls, O. Lider, and M. Schwartz Chondroitin Sulfate-Derived Disaccharide Protects Retinal Cells from Elevated Intraocular Pressure in Aged and Immunocompromised Rats Invest. Ophthalmol. Vis. Sci., March 1, 2007; 48(3): 1181 - 1190. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. C. Chauhan, T. L. LeVatte, K. L. Garnier, F. Tremblay, I.-H. Pang, A. F. Clark, and M. L. Archibald Semiquantitative Optic Nerve Grading Scheme for Determining Axonal Loss in Experimental Optic Neuropathy Invest. Ophthalmol. Vis. Sci., February 1, 2006; 47(2): 634 - 640. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. Huang, J. B. Fileta, A. Dobberfuhl, T. Filippopolous, Y. Guo, G. Kwon, and C. L. Grosskreutz Calcineurin cleavage is triggered by elevated intraocular pressure, and calcineurin inhibition blocks retinal ganglion cell death in experimental glaucoma PNAS, August 23, 2005; 102(34): 12242 - 12247. [Abstract] [Full Text] [PDF] |
||||
![]() |
I.-H. Pang, E. C. Johnson, L. Jia, W. O. Cepurna, A. R. Shepard, M. R. Hellberg, A. F. Clark, and J. C. Morrison Evaluation of Inducible Nitric Oxide Synthase in Glaucomatous Optic Neuropathy and Pressure-Induced Optic Nerve Damage Invest. Ophthalmol. Vis. Sci., April 1, 2005; 46(4): 1313 - 1321. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. V. Bui, B. Edmunds, G. A. Cioffi, and B. Fortune The Gradient of Retinal Functional Changes during Acute Intraocular Pressure Elevation Invest. Ophthalmol. Vis. Sci., January 1, 2005; 46(1): 202 - 213. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Fortune, B. V. Bui, J. C. Morrison, E. C. Johnson, J. Dong, W. O. Cepurna, L. Jia, S. Barber, and G. A. Cioffi Selective Ganglion Cell Functional Loss in Rats with Experimental Glaucoma Invest. Ophthalmol. Vis. Sci., June 1, 2004; 45(6): 1854 - 1862. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Ahmed, K. M. Brown, D. A. Stephan, J. C. Morrison, E. C. Johnson, and S. I. Tomarev Microarray Analysis of Changes in mRNA Levels in the Rat Retina after Experimental Elevation of Intraocular Pressure Invest. Ophthalmol. Vis. Sci., April 1, 2004; 45(4): 1247 - 1258. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Bakalash, A. Kessler, T. Mizrahi, R. Nussenblatt, and M. Schwartz Antigenic Specificity of Immunoprotective Therapeutic Vaccination for Glaucoma Invest. Ophthalmol. Vis. Sci., August 1, 2003; 44(8): 3374 - 3381. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Ishii, J. M. K. Kwong, and J. Caprioli Retinal Ganglion Cell Protection with Geranylgeranylacetone, a Heat Shock Protein Inducer, in a Rat Glaucoma Model Invest. Ophthalmol. Vis. Sci., May 1, 2003; 44(5): 1982 - 1992. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Benozzi, L. P. Nahum, J. L. Campanelli, and R. E. Rosenstein Effect of Hyaluronic Acid on Intraocular Pressure in Rats Invest. Ophthalmol. Vis. Sci., July 1, 2002; 43(7): 2196 - 2200. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Levkovitch-Verbin, H. A. Quigley, K. R. G. Martin, D. Valenta, L. A. Baumrind, and M. E. Pease Translimbal Laser Photocoagulation to the Trabecular Meshwork as a Model of Glaucoma in Rats Invest. Ophthalmol. Vis. Sci., February 1, 2002; 43(2): 402 - 410. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Ahmed, M. Torrado, E. Johnson, J. Morrison, and S. I. Tomarev Changes in mRNA Levels of the Myoc/Tigr Gene in the Rat Eye after Experimental Elevation of Intraocular Pressure or Optic Nerve Transection Invest. Ophthalmol. Vis. Sci., December 1, 2001; 42(13): 3165 - 3172. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Jia, W. O. Cepurna, E. C. Johnson, and J. C. Morrison Effect of General Anesthetics on IOP in Rats with Experimental Aqueous Outflow Obstruction Invest. Ophthalmol. Vis. Sci., October 1, 2000; 41(11): 3415 - 3419. [Abstract] [Full Text] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |