Objective To detect expression of NF-κB in the inner retina and in vestigate the inhibitoryeffect of pyrrolidine dithiocarbamate on retinal neovascularization in rats. Methods The rat models with retinopathy were set up un der the hypoxia condition, and fluorescein fundus angiography (FFA) was used to observe the retinal neovascularization. The expressions of NF-κB in the inner retina in rats with and without neovascularization were detected by immunohisto chemical method. PDTC was intraperitoneally injected in rats with neovascularization to observe the expression of NF-κB in the inner retina and the effect on retinal neovascularization. Results Hypoxia induced NF-κB activation in the retinal glial cells and endothelial cells. But immuno-staining intensity for NF-κB and adhesion molecules were reduced by PDTC intraperitoneal injection. Retin al angiogenesis in rats were suppressed effectively (P＜0.05). Conclusions NF-κB activation correlates with retinal neovascularization closely. PDTC may inhibit the NF-κB activation and prove beneficial in the treatment of ischemic neovascularization. (Chin J Ocul Fundus Dis，2003，19：201-268)
Objective
To investigate the interference effect of nerve growth factor (NGF) on apoptosis of retinal cells in experimental retinal detac hment (RD).
Methods
Twenty seven Sprague-Dawely rats were selected, and the left and right eyes were in the experimental control group and NGF group, respectively. After the RD model was set up by subretinal injection with sodium hyaluronate, 5mu;l NGF（1mu;g/mu;l）was injected into the vitreous body of the right eyes which were in the NGF group; 5mu;l PBS was injected into vitreous body of left eyes which were in the experimental control group. The injection was performed once every 4 days till the end of the observation period. The eye balls of the 27 rats were extrafted 1.5, 3, 6, 12 hours, 1 day, 2, 4, 8 , 16, and 32 days after the RD model was established. Another 2 rats were selected as the normal control, which underwent none of the injections but eyeball extraction at the end of the observation period. TUNEL and transmission electron microscopy were used to detect the apoptosis of the retinal cells. Cell counts and statis tical analysis were used to assess results.
Results
Typical apoptosis cells were observed in the early time of RD. Apoptosis was found in each retinal layers, especially in inner and outer nuclear layers. The number of apoptosis cells increased as the time of RD was prolonged（Plt;0.01）. It was also found that apoptosis cells in NGF group were less than that in the experimenta l control group（Plt;0.01）.
Conclusion
Intravitreous injection exogenous NGF may inhibit the apoptosis of retinal cells in experimental RD.
(Chin J Ocul Fundus Dis, 2006, 22: 333-335)
Objective To investigate the expression of matrix metallo proteinase (MMP)-2 and MMP-9 in rats′optical nerves after extrusion wound. Methods We set up the model of rats with extrusion wound of the optical nerves, detected activity changes of MMP-2 and MMP-9 in the optical nerves by gelatin zymography, identified the attribute by Western blotting, and verified the expression of mRNA of MMP-2 and MMP-9 by reverse transcriptase-polymerase chain reaction (RT-PCR ). Results MMP-2 existed in normal optial nerves and optical nerves with extrusion wound, while MMP-9 was only detected in the latter. The expression of MMP-9 was the highest 1 day after the extrusion wound, while that of MMP-2 was the highest 7 days after the extrusion wound. Conclusions MMP-2 and MMP-9 may participate in the pathological recovery process of optical nerves after extrusion wound. The glial cells in the optical nerves may be one of the sources of MMP-2 and MMP-9. (Chin J Ocul Fundus Dis，2003，19：269-332)
ObjectiveTo observe the inhibitory effect of endostatin (ES) on oxygen-induced retinal neovascularization.MethodsThirtyfour 7-day-old C57BL/6J mice were randomly divided into 3 groups: oxygen-exposed group (12 mice), ES group (12 mice) and the control group (8 mice). The mice in oxygen-exposed and ES group were exposed to (75±5)％ oxygen for 5 days and then back to the normal air. In ES group, 1 μg ES endostatin were injected into vitreous in one eye, while PBS was injected into the other eye as the control 12 and 36 hours after being exposed to oxygen. The mice in the control group were fed in normal circumstance. The changes of retinal neovascularization was examined by fluorescence angiography with fluorescein isothiocyanatedextran. The number of endothelial cells breaking through the internal limiting membrane (ILM) was counted and the inhibitory effects of ES on retinal neovascularization was observed.ResultsCompared with the oxygen-exposed group, the branches of retinal vessels went normal without any un-perfused area in ES group. The number of nuclei of endothelial cells breaking through ILM on each retinal crosssection decreased to (5.39±1.52), which differed much from that in the oxygen-exposed group (22.56±2.13) (plt;0.001).ConclusionES can effectively inhibit the formation of retinal neovascularization in rats and might be a new path of the treatment for proliferative retinopathy.(Chin J Ocul Fundus Dis, 2005,21:314-317)
Objective
To monitor the release of amino acids of the whole retina during and after experimental glaucoma by increasing the intraocular pressure （IOP）．
Methods
Experimental glaucoma was induced in one of the two eyes of rabbits by increasing IOP at 120 mm Hg for 45 min under infusion of saline in anterior chamber；then the pressure was released and the needle inserted into the anterior chamber was removed，this state was maintained for another 45 min．Every 15 min during the experiment 5 rabbits were killed and experimental eyes were enucleated．Aliquots（20 μl）of the retinal extracts（see below）were mixed with ophthaldialdehyde reagent and analysed for amino acid content by the HPLC method of Wangwei，using a 150 mm×4.6 mm,5 μm C18 column．
Results
A large increase in the release of glutamate，but not of the other three amino acids monitored，occurred during initial experimental ocular hypertension．It reached peak value of（111.73±17.46）10-5 mmol/g at 15 min of hypertension．15 min after release of intraocular pressure，again，immediately large and specific increase in the concentration of glutamate was reached to（102.96±51.91）10-5 mmol/g．In eyes subjected to paracentesis of anterior chamber，no difference was found between experimental eyes and controls.
Conclusion
These results suggest that glutamate is triggered by increasing the IOP，and it releases not only during the period of experimental ocular hypertension，but also afterwards.
(Chin J Ocul Fundus Dis, 2002, 18: 146-148)
ObjectiveTo investigate the expression and relation of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in rats with diabetic retinopathy.MethodFifty-five Wistar rats were randomly divided into the control group (10 rats), and 1, 3, and 5-month-diabetes group (15 rats in each diabetes group), and the diabetic models were set up. The expressions of VEGF and bFGF were detected by situ hybridation and immunohistochemistry on retinal paraffin sections.ResultsThe results of situ hybridation showed that expression of bFGF was found in 3-month-deatbtes group with the percentage of 77.8%, and 88.9% in 5-month-deatbtes group; the positive expression of VEGF was not found in 3-month-deatbtes group but in 5-month-deatbtes group with the percentage of 66.7%. Immunohistochemistry indicated that the positive expression of bFGF started in 3-month-deatbtes group with the percentage of 55.6%, and 88.9% in 5-month-deatbtes group; the percentage of the expression of VEGF was 33.3% in 3-month-deatbtes group and 88.9% in 5-month-deatbtes group.ConclusionThe expression of VEGF occurs after the expression of bFGF in rats with DR.(Chin J Ocul Fundus Dis, 2005,21:37-40)
PURPOSE:To measure the concentration changes of tumor necrosis factor a (TNF-alpha;)in vitreous during the development of experimental PVR induced by macrophages and explore the initial and mediated factors which stimulate the
cellular proliferation.
METHODS:Rabbit PVR model was induced by macrophages and the vitreous was taken at the 7th,14th,21st and 28th day and 4 eyes in each group. The TNF-alpha; levels in vivreous of the above examinated and control eyes were
measured with an ELISA kit.
RESULTS:The TNF-alpha; level in the vitreous reached its peak 434mu;g/ml at 21st day in the mod-el, then rappidly decreased to 122mu;g/ml at 28th day. CONCLUSION:The changes of TNF-a in the vitreous of the PVR model were parallel to the natrual phases of the development of PVR,indicating TNF-alpha; may play an important role in initiating and mediating the inflammation and cellular proliferation in the vitreous.
（Chin J Ocul Fundus Dis,1997,13: 231-233）
Objective To investigate if insulin can affect the expression of vascular endothelial growth factor (VEGF) in the retina of streptozotocin-induced diabetic rats. Methods A total of 60 male SpragueDawley rats were randomly divided into sodium citrate buffer control group (CIT-CON, n=30) and STZ-induced diabetic group (STZ-DM, n=30). At the 16th week, 24 rats from CIT-CON group at random were randomly divided to group A (sodium citrate buffer control group, n=12) and group B (sodium citrate buffer plus insulin group, n=12). The remaining 6 rats from as CIT-CON group served as negative control. At the same time, 24 rats from STZDM group at random were randomly divided to group C (STZinduced diabetic group, n=12) and group D (STZ-induced diabetic plus insulin group, n=12). The remaining 6 rats from STZ-DM group also served as negative control. 4 IU of insulin was injected subcutaneously to rats of group B and D. Immunohistochemistry, Western blot and Real-time polymerase chain reaction (RT-PCR) were used to measure the expression level of VEGF protein and mRNA respectively. RESULTS Insulin significantly increased the VEGF mRNA (7.71plusmn;0.25 vs 5.36plusmn;0.37, t test Plt;0.05) and protein expression (0.4925plusmn;0.0122 vs 0.4272plusmn;0.0110, t test Plt;0.05) in the retina of CITCON rats. However, in retina of STZDM rats, insulin had no effect on VEGF mRNA (8.92plusmn;0.27 vs 9.05plusmn;0.28, t test, Pgt;0.05) and protein expression (0.5152plusmn;0.0109 vs 0.5099plusmn;0.0100, t test Pgt;0.05). Conclusions Insulin had no effect on VEGF expression in the retina of STZ-DM rats.
Objective
To investigate the effect of suppression of ischemia-induced retinal neovascularization by VEGF antisense oligodeoxyribonucleotides.
Methods
Mouse models of hyperoxia-induced ischemic retinopathy were established. Retrobulbar injections were performed with VEGF antisense oligodeoxyribonucleotides or NS in 4 groups:normal control and various doses respectively. The nuclei of new vessel buds extending from the retina into the vitreous in differ ent groups were counted and compared under the light microscope.
Results
There were plenty of new vessel buds in the eyes of mice in hyperoxic condition., while the number of the nuclei of new vessel buds is less in the murine eyes with retrobulbar injection of VEGF antisense oligodeoxyribonucleotides,especially the nuclei were redused with 59.3% in eyes with large dose.
Conclusion
The proliferation of retinal new vessel may be suppressed by using the retrobulbar injection of VEGF antisense oligodeoxyribonucleotides.
(Chin J Ocul Fundus Dis, 2001,17:141-143)
Purpose
To evaluate the prostag landins(PG) levels and to identify the effect of dexamethasone(DXM) on PG in response to photochemical insult in rat retina.
Methods
The experiments were performed on 36 SD rats which were separated into two groups,control and treated groups,and the latter received daily intraperitoneal injections of DXM (1 mg/kg) for 5 consecutive days,starting 3 days before light exposure.The animals were continually exposed to green fluorescent light(510-560 nm)with an illuminance level of (1900plusmn;106.9)lx for 24 hrs.The retinal concentration of PGE 2 and 6-keto-PGF1alpha; were tested at 6hrs,1,3,7 and 14 days after light exposure.
Results
The PGE2 and 6-keto-PGF1alpha; levels of the control groups (37.50plusmn;2.75,48.06plusmn;4.0 4,81.90plusmn;4.89) pg/mg and (4.68plusmn;0.69,7.50plusmn;0.57,10.40plusmn;0.71) pg/mg had significantly higher values than those of the treated rats(20.60plusmn;4.28,37.36plusmn; 3.34,54.85plusmn;4.57) pg/mg and (2.50plusmn;0.59,4．68plusmn;0.81,6.87plusmn;1.10)pg/mg (Plt;0.01) after 6 hrs,1 and 3 days light exposure respectively.
Conclusion
By inhibition of PG synthesis,the DXM may play an ameliorative effect on retinal photochemical injury of rats.
(Chin J Ocul Fundus Dis,1999,15:94-96)
