Purpose:To set up the Sharma’s chronic intraocular hypertension model and investigate the intraocular pressure (IOP) as well as the optic nerve damage of this model in rat. Methods:The operations of the chronic intra...Purpose:To set up the Sharma’s chronic intraocular hypertension model and investigate the intraocular pressure (IOP) as well as the optic nerve damage of this model in rat. Methods:The operations of the chronic intraocular hypertension model were performed as described by Sharma in 60 male Lewis albino rats. IOP was measured using the Tono-Pen XL immediately after surgery and then at 5 day, 2 week or 4 week intervals. Cresyl violet staining of whole-mounted retinas was used to label retinal ganglion cells (RGCs), then RGCs were counted. Paraphenylenediamine (PPD) staining was performed in the semi-thin cross sections of optic nerve of rat, in order to know whether the axons of optic nerve were degenerated or not. Results:There were 47 rats with higher IOP after the episcleral veins cauterized in 60 rats. The ratio of elevated IOP was 78.3%. The IOPs were stable in 4 weeks. After cresyl violet staining, the RGCs loss was 11.0% and 11.3% was found in the central and peripheral retina respectively after 2 weeks of increased IOP. After 4 weeks of increased IOP, the loss of RGCs was 17% for the central retina and 24.6% for the peripheral retina. In the retinas without higher IOP, there was no loss of RGCs. PPD staining showed that optic nerve of rat with about 5.3% damage of axons located at the superior temporal region. Region of affected optic nerve 1 mm posterior to the globe by light microscope showed evidence of damaged axons with axonal swelling and myelin debris. Conclusion:Sharma’s chronic intraocular hypertension model is a reproducible and effective glaucoma model, which mimics human glaucoma with chronically elevation IOP and induced RGCs loss and damage of optic nerve. Eye Science 2004;20:25-29.展开更多
文摘Purpose:To set up the Sharma’s chronic intraocular hypertension model and investigate the intraocular pressure (IOP) as well as the optic nerve damage of this model in rat. Methods:The operations of the chronic intraocular hypertension model were performed as described by Sharma in 60 male Lewis albino rats. IOP was measured using the Tono-Pen XL immediately after surgery and then at 5 day, 2 week or 4 week intervals. Cresyl violet staining of whole-mounted retinas was used to label retinal ganglion cells (RGCs), then RGCs were counted. Paraphenylenediamine (PPD) staining was performed in the semi-thin cross sections of optic nerve of rat, in order to know whether the axons of optic nerve were degenerated or not. Results:There were 47 rats with higher IOP after the episcleral veins cauterized in 60 rats. The ratio of elevated IOP was 78.3%. The IOPs were stable in 4 weeks. After cresyl violet staining, the RGCs loss was 11.0% and 11.3% was found in the central and peripheral retina respectively after 2 weeks of increased IOP. After 4 weeks of increased IOP, the loss of RGCs was 17% for the central retina and 24.6% for the peripheral retina. In the retinas without higher IOP, there was no loss of RGCs. PPD staining showed that optic nerve of rat with about 5.3% damage of axons located at the superior temporal region. Region of affected optic nerve 1 mm posterior to the globe by light microscope showed evidence of damaged axons with axonal swelling and myelin debris. Conclusion:Sharma’s chronic intraocular hypertension model is a reproducible and effective glaucoma model, which mimics human glaucoma with chronically elevation IOP and induced RGCs loss and damage of optic nerve. Eye Science 2004;20:25-29.