Ras homolog family (Rho)/ Rho-associated coiled-coil kinase (ROCK) signaling pathway widely exists in human and mammal cells, which is closely related to inhibition of repair after optic nerve damage. The expression level of Rho/ROCK signaling pathway-related proteins is up-regulated in glaucoma, and related with the death of retinal ganglionic cell (RGC) and the axon activity. ROCK inhibitors can protect the surviving RGC and promote axon extension with a dose-dependent manner. ROCK inhibitors also can inhibit glial scar formation, lower intraocular pressure and inhibit inflammatory response to some degrees. Rho/ROCK signaling pathway correlates with the optic nerve disease progression, and ROCK inhibitors hope to become a new therapeutic drug.
Objective To evaluate the expressive varieties of Nogo-A mRNA in injured optic nerves of rats. Methods Reverse transcription polymerase chain reaction (RT-PCR) method was used to hemi-quantitatively analyze the levels of Nogo-A mRNA in the optic nerves 3, 7, 9, 15, 21, and 25 days respectively after injury.Results The level of the expression of Nogo-A mRNA was low in the normal optic nerves, while it was significantly high in the optic nerves 3 days after in jury, and kept the high level still after 25 days.Conclusion The expression of Nogo-A mRNA in injured optic nerves is increased. (Chin J Ocul Fundus Dis,2003,19:201-268)
ObjectiveTo observe the clinical therapeutic effects of radial optic neurotomy (RON) for central retinal vein occlusion (CRVO).MethodsThe clinical data of 12 patients (12 eyes) with CRVO who had undergone RON were retrospectively analyzed. The patients were examined by visual acuity and fundus examination, photography, fundus fluorescein angiography, and optical coherence tomography (OCT). The visual acuities of all of the 12 eyes with severe hemorrhage and retinal edema were less than 0.1. A microvitreoretinal blade or CRVO knife was penetrate into the nasal side of the optic disk, and the incision reached the cribriform plate and even the back, and then dissected at the nasal side of the cribriform plate. The postoperative follow-up period lasted 2 to 15 months with the mean of 6.5 months, and the visual acuity, the condition of visual field and ocular fundus of the eyes undergone the surgery were observed.ResultsIn 12 eyes undergone RON successfully, the visual acuity after the surgery improved more or less in 9 (75%), and more than or up to 0.1 in 6. The results of the examinations showed that the retinal edema and hemorrhage disappeared gradually, varicosity mitigated, retinal serous detachment mitigated or disappeared, and macular cystoid edema faded; macular fovea recovered in 3 eyes, optic nerve had a hemorrhage during the operation in 3 eyes, and the dissected part of optic nerve became atrophic afterward in 4.ConclusionsRON performed at the edge of the nasal side of the optic disc is safe and effective, which may improve the visual acuity of the eyes with CRVO and mitigate retinal hemorrhage and edema.(Chin J Ocul Fundus Dis, 2005,21:10-12)
Objective To observe the clinical manifestations and the effect factors of thyroid-associated ophthalmopath (TAO) with optic neuropathy. Methods The clinical data of 62 cases (120 eyes) of TAO with optic neuropathy diagnosed in 1994-2001 were retrospectively analyzed. Results The incidence of TAO with optic neuropathy was 18.3% in all the simultaneous TAO inpatients, and was more frequently found in the male than in the female ones. The incidence of TAO with optic neuropathy was correlated with orbitono-increase, ocular myopathy, hypertension, hyperlipemia, diabetes, and cardiopathy (P<0.0000), but not with exophthalmos, intraocular pressure, and the disease course of TAO (Pgt;0.05). In 62 patients with the methylprednisolone pulse therapy, the visual acuity improved in 33 (29.0%), improved while the treatment but decreased after stop treating in 29 (24.2%), and no changes in 58 (46.8%). In 63 eyes undergone orbital decompression with methylprednisolone pulse therapy, 59 (93.7%) had better visual acuity. Conclusion The incidence of TAO with optic neuropathy was correlated with orbitono-increase, ocular myopathy, hypertension, hyperlipemia, diabetes, and cardiopathy. Met hylprednisolone pulse therapy and orbital decompression are the effective measures for TAO with optic neuropathy. (Chin J Ocul Fundus Dis,2004,20:142-144)
Objective To study the expression and its significance of bcl-2 associated death (bad) gene in human optic nerves from traumatic atrophic eyeballs. Methods The optic nerves from 8 normal human donor eyes and 31 traumatic atrophic eyes were studied by immunohistochemistry technique. Results Bad protein was positively expressed in the normal optic nerve myelin sheath and residual myelin portions of optic nerve tissues from traumatic atrophic eyes. The expression of bad protein in the residual portions of myelin sheath was stained significantly ber than that in normal optic nerves (P<0.05)。The pathological durations for ocular atrophy was not co-related with the quantites of expression of bad protein. There was no significant difference between pathogenic causes of ocular atrophies and the quantites of bad expression (P>0.05). Conclusion Bad might possess the function of promoting the optic nerve atrophy processes in traumatic atrophic eyes. (Chin J Ocul Fundus Dis, 2002, 18: 276-278)
Objective To investigate the mRNA expression of ciliary neurotrophic factor on the retina during injury and repair of optic nerves in rats. Methods Thirty-five healthy SD rats were randomly divided into 3 groups: 5 in the control group, 15 in the simply transected optic nerve group and 15 in the optic nerve-sciatic nerve anastomosis group. The simply transected and optic nerve-sciatic nerve anastomosed models were set up, and the retinal tissues of all of the rats were taken out after 3, 7 and 14 days, respectively; and the mRNA expression of CNTF in the 3 groups were observed by semiquantitative reversal transcription-polymerase chain reaction method. Results A minimum expression of CNTF mRNA was found in the retinae of the control group, and the increased rates of expression were found in the retinae of the simple transection of optic nerve group with the increase rate of 100%, 594%, and 485% on the 3rd, 7th, and 14th day respectively after the operation, while in optic nerve-sciatic nerve anastomosis group, the increase rates were found to be 258%, 752% and 515% on the 3rd, 7th, and 14th day respectively after the operation. Conclusion Retinal neurons can respond to axonal reaction of retinal ganglion cells by up-regulate endogenous CNTF after the injury of the optic nerves, which may provide a theoretic base for the application of the exogenous CNTF. (Chin J Ocul Fundus Dis,2004,20:355-357)
Objective To observe the difference between blood brain barrier and blood optic nerve barrier. Methods Twenty normal male SD rat sprime; optic nerve including prelaminar region, lamina cribrosa, retro-laminar region, intraorbital portion, intracanalicular portion, and intracranial portion respectively,and cerebral cortex were removed separately. Ultrastructure of endothelial cells was observed by electron microscopy. Immunohistochemical staining was used to detect the expression of transferrin receptor (OX-26) and metalloproteinase inducer (OX-47) and extravasation of fibrinogen around microvessels. Results The results of electron microscopy showed that endothelial cells of microvessels in each portion of optic nerves and cerebral cortex did share the same tight junctions. However, the number of plasmalemmal vesicles in prelaminar region was significantly more than that in cerebral cortex(P<0.05);there was no significant difference between other parts of optic nerves (lamina cribrosa, retro- laminar region, intraorbital portion, intracanalicular portion, and intracranial portion)and cerebral cortex in the number of the plasmalemmal vesicles(Pgt;0.05). By immunohistochemical staining,the endothelial cells of microvessels in the prelaminar region showed no expression of the OX-26 and OX-47,but extravasation of fibrinogen around microvessels was found; b positive expression of OX-26 and OX-47 was observed in the endothelial cells of the microvessels in other parts of optic nerves (lamina cribrosa, retro-laminar region, intraorbital portion, intracanalicular portion, and intracranial portion) andcerebral cortex, and no fibrinogen was seen aro und the microvessels. Conclusions There is a significant difference between the endothelial cells of the microvessels in prelaminar region and cerebral cortex in the ultrastructure, markers expression, and permeability, so the microvessel s in prelaminar region lacks the typical blood brain barrier characteristics.The microvessels in other parts of optic nerves (lamina cribrosa, retro-laminar region, intraorbital portion, intracanalicular portion, and intracranial portion) have blood brain barrier properties due to its similar specialties as which in cerebral cortex. (Chin J Ocul Fundus Dis, 2006, 22: 390-393)
Objective To observe the affection of optic nerve under acute ocular hypertension and the effect of protection of bFGF on optic nerve. Methods BSS was perfused into anterior chamber of rabbits to increase the intraocular pressure to cause retinal ischemia. A computer image analysis system was used to count the optic nerve axons.Eyes were intravitreally injected with bFGF and then the number of optic nerve axons of the normal rabbits,and hypertension with and without bFGE treatment groups were counted respectively. Results The number of optic nerve axons in ocular hypertension eyes was less than the normal eyes(P=0.00003).The bFGF treated eyes had more optic nerve axons than the controls(P=0.0078). Conclusions The acute ocular hypertension may cause the loss of the nerve axons,and bFGF may be effective in protecting optic nerve in acute ocular hypertension. (Chin J Ocul Fundus Dis,2000,16:94-96)
Objective To analyze the new primary mutation in Chinese people with Leberprime;s hereditary optic neuropathy (LHON). Methods Genomic DNA was collected from 260 suspected LHON patients and 100 normal healthy persons. The mitochondria DNA mutation at nucleotide position (NP) 15257 and the hot spot (14452-14601 bp) of ND6 gene which include the mutations at NP (14482, 14498, 14568, 14596, 14495, and 14459) were screened by using polymerase chain reaction (PCR), heteroduplex-single strand conformation polymorphism (HA-SSCP) and restriction fragment length polymorphism (RFLP) analysis and sequencing. Primary mutation spectrum of Chinese race was analyzed. Results Eight kinds of polymorphism of mitochondria DNA were found in 260 suspected LHON patients and 100 normal healthy persons, including NP 14488C, 14518G, and 14617G which hadnrsquo;t been reported (http://www.mitomap.org/). No mutation at NP 15257, 14482, 14498, 14568, 14596, 14495, and 14459 was found. Conclusion The NP 15257A may not be the primary mutation in Chinese. Because of the race difference, 14452-14601 bp in ND6 gene may not be the hot spot in Chinese patients with LHON, and other hot spots may exist. (Chin J Ocul Fundus Dis, 2006, 22: 82-85)