PURPOSE: To explore the pathogenesis of anisometropic and amblyopias. METHODS:To carry out on monocular and binocular atropinized cat models during the developmental period for anisometropia and ametropia ,and measure the cytosomal sectional area and some parameters of the dendric field from the dorsal lateral geniculate nuclei (dLGN)of adult cats by using Golgi-Cox staining. RESULIS:The changes of cytosomal sectional areas and parameters about dendric fields in the dLGN of experimental cats were as following:significant differences between cells of dLGN's A1 lamina by the monocular atropinized eyes and normal ones, binocular atropinized eyea and normal ones;no significant difference between tbat driven by the monoular and binocular atropinized eyes. CONCLUSIONS:There might be resemble pathogenesis between anisomelropic and ametropic amblyopias. (Chin J Ocul Fundus Dis,1996,12:153-156)
Objective To investigate the effects of lights with different wavelength on the retina of rd12 and C57BL/6J mice. Methods Thirty two rd12 mice and C57BL/6J mice were randomly divided into the control group, white light group, midwavelength light (505 nm) group and shortwavelength light (405 nm) group, with eight mice in each group. Besides the control group, other groups were exposed to cycle illuminations [12 hours dark, 12 hours (800plusmn;130) Lux] for seven days to establish the model of retinal light damage. Electroretinogram (ERG) responses of all mice were recorded at the day before illumination and 1st, 4th and 7th days after illumination. The eyes were enucleated at 7th days after illumination to assess levels of reactive oxygen species (ROS), expression of peroxiredoxin 6 (PRDX6), and activity of caspase-3. Results ERG amplitudes of all groups declined gradually in C57BL/6J mice, and the most significant effects was found in the short-wavelength light group. The amplitudes of photopic b-wave were significantly different at 1st, 4th and 7th days (F=4.412, 5.082, 9.980;P<0.01). The amplitudes of cone b-wave of the four groups decreased to (85plusmn;10) %, (70plusmn;19) %, (57plusmn;22) % and (46plusmn;19) % at 7th days, respectively, and were significantly different between white light group and short-wavelength light group(t=3.19,P<0.01). The levels of ROS were significantly different in rd12 mice (F=16.08,P<0.01), and elevated obviously in shortwavelength light group. The expressions of PRDX6 of retina were significantly different in rd12 mice (F=7.214,P<0.05), and were decreased obviously in short-wavelength light group. The caspase-3 relative activity was significantly different in rd12 retina (F=7.530,P<0.05); but there was no significant difference in C57BL/6J mice (F=3.625, 1.993, 1.133; P>0.05).The caspase-3 relative activity were significant different between rd12 mice and C57BL/6J mice in short wavelength light group (t=5.474,P<0.05). Conclusions Short-wavelength light can induce retinal damage of mouse retina, especially in rd12 mouse. The retinal light damage possibly relates to the oxidative damage.
Objective To build animal models of keloid by method of tissue engineering and to discuss the feasibility of using it in clinical and lab researches. Methods Fibroblasts(FB) were isolated from keloids and cultured. The seventh and eighth generation of the cultured FBs were inoculated into the copolymers of polylactic acid and polyglycolic PLGA. After being cultured in rotatory cell culture system (RCCS)for 1 week,the FB was transplanted into athymic mice. The specimens were obtained 4 weeks and 8 weeks and examined histologically. Results All mice survived.The collagen patterns of all keloids were pressed in every specimen obtained 8 weeks. Fibrocytes andFB were observed in specimens by electronic microscope. There were abundent rough endoplasmic reticulum (RER) in FB, which indicated that FB’s capability of synthesizing and secreting collagen was preserved and the cellular characteristicwas remained. Conclusion There is a good affinity between PLGAand FB. The composition of PLGA and FB can form keloids in athymic mice,so that it deserves further researching and developing.
Objective:To observe the protective effect of ginkgo bilo ba extrac t (EGb 761), a free radical scavenger, on the photoreceptor cells after lighti nduced retinal damage. Methods:Seventytwo female SpragueDa wley (SD) rats we re randomly divided into 4 groups: normal control group, lightinduced retinal da m age model group, model+physiological saline group, and model+EGb 761 group, with 18 rats in each group. All of the rats except the ones in the control group were exposed to white light at (2740plusmn;120) lx for 6 hours after the dark adap tation for 24 hours to set up the lightinduced retinal damage model. Rats in m o del + physiological saline group and model+EGb 761 group were intraperitoneall y injected daily with physiological saline and 0.35% EGb 761 (100 mg/kg), respec tively 7 days before and 14 days after the light exposure. Apoptosis of photorec eptor cells was detected 4 days after light exposure; 7 and 14 days after light exposure, histopathological examination was performed and the layer number of ou ter nuclear layers (ONL) on the superior and inferior retina was counted. Results:Four days after light exposure, the apoptosis of photorecep tor cells was fou nd on ONL in model, model+ physiological saline and model+EGb 761 group, and w as obviously less in model + EGb 761 group than in model and model+physiologic al saline group. Seven days after light exposure, the layers of ONL on the super ior retina were 3 to 4 in model and model+physiological saline group, and 7 to 8 in model+EGb 761 group; the mean of the layer number of ONL in model+EGb 761 group (6.92plusmn;0.82) was less than that in normal control group (8.40plusmn;0.95) (t=-1.416, P<0.05), but significantly more than that in model (5.96 plusmn;1.36 ) and model+physiological saline group (5.90plusmn;1.40)(t=1.024, 1.084; P<0.05). Fourteen days after light exposure, the layers of ONL on the superior retina were 0 to 1 in model and model+physiological saline group, and 3 to 4 i n model+EGb 761 group. The mean of the layer number of ONL in model+EGb 761 group (5.5 2plusmn;1.06) was significantly more than that in model (3.44plusmn;2.15) and model + physiological saline group (3.37plusmn;1.91) (t=2.082, 2.146, P<0.05). Conclusion:EGb 761 can partially inhibit the apoptosis of pho toreceptor cells, thus exert protective effect on photoreceptor cells.
Objective To inverstingate the effect of perfluorohexyloctane(F6H8)to the retina of rabbit eyes. Methods Fifteen vitrectomized New Zealand white rabbits were injectedF6H8(experiment group,12 rabbits ) and BSS(control group,3 rabbits) into vitreous cavity.Slit-lamp biomicroscopy and indirect ophthalmoscopy were performed pre- and postoperatively in all the eyes.Histopathological examination was done after the rabbits were sacrificed at the end of the study. Results A large clear balb was formed after intravitreal injection of theF6H8 in the vitreous was injected and no retinal detachment and cataract were found.The OPL was edematous and then thinned out in 4th week in experimental group.Degenerating cells was found in inner and outer nuclear layers.Cellular vaculoar degeneration was present in TEM. ConclusionF6H8 in vitreous cavity may cause significant side effects on retina,we could not recommend it to be used as an intraocular temponade.
Objective To investigate the inhibitory effects of IBI302 on experimental choroidal neovascularization (CNV). Methods Affinity of IBI302 to vascular endothelial growth factor (VEGF) family cytokines (including VEGF-A165, VEGF-A121 and placental growth factor PlGF) and complements (C3b, C4b) was determined by enzyme-linked immunosorbent assay (ELISA). The antagonist effect of IBI302 on VEGF was measured by proliferation, migration and tube formation tests of human umbilical vein endothelial cells (HUVEC). The anti-complement activity of IBI302 was measured by hemolysis test mediated by complement classical pathway and alternative pathway. Rhesus laser-induced CNV model was divided into 5 groups including model control group, bevacizumab group, IBI302 0.25 mg group, IBI302 0.50 mg group and IBI302 1.25 mg group. Fluorescein angiography and optical coherence tomography were performed on these monkeys at 14 and 28 days after drug delivery to observe the fluorescein leakage area and retinal thickness. The aqueous VEGF concentration was measured at 29 days after drug delivery. Results IBI302 showed good affinity to VEGF-A165, VEGF-A121 and PlGF, as well as C3b and C4b. IBI302 significantly inhibited the proliferation, migration and tube formation of HUVEC induced by VEGF-A165. IBI302 inhibited the hemolysis induced by complements obviously. At 14 and 28 days after drug delivery, the area of fluorescein leakage and retinal thickness in IBI302 0.25 mg group, IBI302 0.50 mg group, IBI302 1.25 mg group were reduced. The differences of the area of fluorescein leakage and retinal thickness in three IBI302 groups were not significant (P > 0.05). At 29 days after drug delivery, the VEGF concentration in the aqueous of rhesus monkey in bevacizumab group [(38.644±6.521) pg/ml] was decreased than that in model control group [(94.203±17.360) pg/ml], the difference was significant (P < 0.05). The VEGF concentration in the aqueous of rhesus monkey in three IBI302 groups were less than 31.300 pg/ml. Conclusion IBI302 inhibited experimental CNV through blocking the activity of VEGF and complement.
Objective To construct small hairpin RNA (shRNA) expression plasmid targeting rat opticin gene.Methods Four pairs of opticin oligonucleotides were synthesized and inserted into the plasmid vector, resulting into four plasmids: shRNA-1, shRNA-2, shRNA-3 and shRNA-4. Then the four constructed shRNA expression vectors and empty vector were transfected into rat ciliary non-pigment epithelium (NPE) cells by lipofectmaine 2000. Nontransfected NPE cells were set as control group.The expression of opticin mRNA and protein were measured by Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot respectively.Results The opticin mRNA expression of the shRNA-1,shRNA-2,shRNA-3,shRNA-4 group were decreased compared with the control group (F=10.239,P=0.000);the inhibitory rate were 85.7%,62.87%,54.87% and 48.77% respectively.The opticin protein expression of the shRNA-1,shRNA-2,shRNA-3,shRNA-4 group were also decreased compared with the control group (F=17.870,P=0.000);the inhibitory rate were 78.7%,34.6%,31.1% and 16.8% respectively.Conclusions The shRNA-1 expression plasmid has most potent inhibitory effect on opticin expression in rat ciliary NPE cells.
ObjectiveTo investigate the effects of transforming growth factor-β (TGF-β) in choroidal neovascularization (CNV) induced by laser in mice. Methods Eighty male C57BL/6J mice at the age of 6-8 weeks old were randomly divided into the normal control, photocoagulation model, photocoagulation with phosphate buffered saline (PBS control group) and photocoagulation with TGF-β receptor inhibitor groups (TGF-β receptor inhibitor group), twenty mice of each group. Fundus argon laser photocoagulation was performed in the photocoagulation model group, PBS control group and TGF-β receptor inhibitor group to induce CNV. One week, two, three and four weeks after the laser procedure, fundus fluorescein angiography (FFA) was carried out in the normal control or photocoagulation model groups to observe CNV formation dynamically. Western blot was used to analyze the expressions of TGF-β in the retina from the mice of normal control or photocoagulation model groups, and VEGF or TNF-α in the retina of normal control, PBS control or TGF-β receptor inhibitor groups. The CNV areas of each group were evaluated by using fluorescein stain on retinal pigment epithelium (RPE)/choroid flat mounts after two weeks of photocoagulation. ResultsThe FFA results showed the retinal vessels centered on the optic disc and arranged radially, while the choroidal vascular present network distribution in the normal control mice. Significant leakage of fluorescein showed discoid strong fluorophore in photocoagulation sites of retina at one week after photocoagulation. The quantitative analysis results of Western blot demonstrated that the TGF-β protein expression levels in retina of photocoagulation model mice gradually increased with time passing. The protein expression levels of TGF-β were significant differences in the photocoagulation model group comparing with the normal control group (F=13.042, P < 0.05). The protein expression levels of TNF-α (F=14.721, 17.509) and VEGF (F=18.890, 11.251) increased significantly in retina of PBS control or TGF-β receptor inhibitor groups when compared with that of normal control group at one week, two, three and four weeks after photocoagulation, and the differences were both statistically significant (P < 0.05). Compared with PBS control group, the protein levels of TNF-α and VEGF in retina from TGF-β receptor inhibitor group were significantly reduced, the differences was statistically significant (F=21.321, 16.160, P < 0.05). Two weeks after laser photocoagulation, a distinct reduction in CNV lesion size in the TGF-β receptor inhibitor group mice when compared to PBS or normal control groups, the differences was statically significant (F=4.482, P < 0.05). ConclusionTGF-β may promote CNV formation by up-regulating both TNF-α and VEGF protein expressions, the application of its specific inhibitor is able to reduce CNV progression.
Objective To explore the key technique of allogeneic whole pancreaticoduodenal transplantation (WPDT) in rats. MethodsWPDT model was established between Lewis rats as donors and Wistar rats (with type 1 diabetes mellitus) as recipients. End to side anastomosis was performed in abdominal aorta of donors and recipients. The portal vein of the graft was anastomosed with the recipients left renal vein by cuff technique. And side to side anastomosis was made between the graft duodenum and the host jejunum. ResultsForty-four of 50 rats were successfully performed WPDT. Amongthem, 8 rats died in postoperative 3 days, the survival time of residual 36 rats was 6-16 days, with an average of (10.45±3.30) days. The peak of death appeared on day 7-10 after operation. The typical acute rejection in pathological changes were observed on day 7. ConclusionSkilled microsurgical techniques and emphasis on details are important to establish WPDT model.