From the results of this experiment, it showed that the implanted tendon was gradually extruded from the tibia hole and attached to the periosteum. The dominant breeding of tissue cells, cytodynamics, the perimeter ratio of tendon/bone and the effect of revascularization were discussed in detail.
Objective To observe the inhibiting effects of alginate sodiumretinoic acid(AGS-RA)microspheres release system on the laser coagulationinduced subretinal proliferation.Methods RA were dissolved by absolute alcohol,then mixed with 1.5% AGS and made into AGSRA microspheres by a microcapsule electrostatic generator. The parameter of laser injury include irradiation time (0.20 s),spot diameter (200 mu;m) and output power (420 mW).Thirty pigmented rabbits were randomly divided into 3 groups (laser injury,experimental and control group).After laser coagulation,AGSRA or blank microspheres were immediately injected into the vitrous of experimental and control rabbits respectively.The height,width and area of 6 retinal spots of laser coagulation at each timepoint were analyzed histopathologically with serial retinal sections at 1,2,3,4,and 6 weeks after laser coagulation.Results Histopathological examination showed that there were morphological and distribution changes of retinal cells in all layers, and localized fibroblasts proliferation in the retina after laser injury. The laserinduced responses in experimental group were much milder(P<0.01), while the laser injury group and control group have same width(P>0.05)and height/area of laser spots(P>0.05).Conclusion AGSRA release system can alleviate the subretinal proliferate after laser injury.
ObjectiveTo evaluate the inhibitory effect of small interfering RNA (siRNA) targeting peroxisome-proliferator-activated receptor-γcoactivator-1α(PGC-1α) on retinal neovascularization in the mouse. MethodsEighty seven-day-old C57BL/6J mice were divided into normal group, model blank group, model control group and PGC-1αsiRNA group, twenty mice in each group. Mice in the normal group were kept in normal room air. Mice in the model blank group, model control group and PGC-1αsiRNA group were induced for retinal neovascularization by hypoxia. Liposome with PGC-1αsiRNA (1 μl) and liposome with negative control siRNA (1 μl) were injected into the vitreous in the PGC-1αsiRNA group and model control group respectively when mice were moved out to room air from the cabin (Postnatal 12). No injection were performed in the model blank group. At postnatal 17, fluorescein angiography was used to assess the vascular pattern.The proliferative neovascular response was quantified by counting the nuclei of new vessels extending from the retina into the vitreous in cross-sections. PGC-1αand vascular endothelial growth factor (VEGF) level in retina were measured by real-time polymerase chain reaction (real-time PCR) and Western blot. Inhibition efficiency of PGC-1αsiRNA on PGC-1αand VEGF was calculated. ResultsMice in the normal group showed reticular distribution of retinal blood vessels. Central nonperfused retina, neovascular tufts and fluorescein leakage were seen in the model blank group and model control group. Neovascular tuft and fluorescein leakage were decreased in the PGC-1αsiRNA group compared to the model blank group and model control group. The neovascular nuclei were increased in the model blank group and model control group compared to the normal group (P < 0.05). The neovascular nuclei were decreased in the PGC-1αsiRNA group compared to the model blank group and model control group (P < 0.05). The expression of PGC-1αmRNA and protein in retina was increased significantly in the model blank group and model control group as compared with normal group, while decreased 54% and 53% respectively in the PGC-1αsiRNA group as compared with model blank group and model control group (P < 0.05). The expression of VEGF mRNA and protein in retina was increased significantly in the model blank group and model control group as compared with normal group, while decreased significantly in the PGC-1αsiRNA group (decreased 48% and 40% respectively) as compared with model blank group and model control group (P < 0.05). ConclusionsIntravitreal injection of PGC-1αsiRNA mediated by liposome can inhibit retinal neovascularization in the mouse effectively.
Objective To investigate the temporal and spatial expression pattern of Caspase3、Bax and Bclxl in NmethylNnitrosourea (MNU) damaged rat retina. Methods Twenty-four 50 dayold female Sprague-Dawley rats (n=24) received single intraperitoneal injection of MNU 40 mg/kg and were examined at 1, 3, 7 and 10 days after MNU treatment (6 rats sacrificed at each timepoint). As control, six rats were injected with saline (5 ml/kg) and sacrificed 3d after injection. Expressions of Caspase-3 and bax and bcl-xl were detected by RTPCR and immunofluorescence assays, photoreceptor cell apoptosis was measured by terminal deoxynucleotidyl transferasemediated deoxyuridine triphosphatedigoxigenin nick-end labeling (TUNEL). Results Animal models were successful established and confirmed by pathological studies. RTPCR results indicated that caspase3 and bax upregulated at 1 d (caspase-3 RA =83.23plusmn;8.11,P= 0.009; bax-RA=72.73plusmn;9.46,P=0.004) and peaked at 3 d (caspase-3 RA=140.48plusmn;18.40,P=0.000;bax-RA=102.36plusmn;13.97,P=0.001)compared with control (caspase-3 RA=62.45plusmn;7.65; bax-RA =46.53plusmn;4.41). Bcl-xl expression increased and peaked at 3d (3d RA=79.83plusmn;5.58, P=0.000 vs control 45.98plusmn;3.06). It was noted that the ratios of bax / bclxl expression at 1 d, 3 d and 7 d after MNU injection were enhanced (1 d 1.15plusmn;0.14, P= 0.143; 3 d 1.28plusmn;0.16, P=0.001; 7 d 1.17plusmn;0.08, P= 0.079, vs control 1.01plusmn;0.09), and at 3 d the ratio reached the peak, whereas at10 d bax / bcl-xl ratio (0.73plusmn;0.07, P= 0.001) was decreased compared with the control. Immunofluorescence assays demonstrated that the changes of bax, bclxl and caspases3 protein expressions coincided with their RTPCR results respectively. The Bax positive cells were detected in the outer nuclear layer; while caspase3 and bclxl positive cells emerged in several layers of retina included the pigment epithelium layer, the photoreceptor cell inner segments, the outer nuclear layer, the outer plexiform layer, the inner plexiform layer and the ganglion cell layer. Photoreceptor cell apoptosis was only detected in the outer nuclear layer and peaked at 3 d in MNU treated rats (AI= 76.97plusmn;5.83, P= 0.000 vs control 0.00 plusmn; 0.00). Conclusions These data suggest that bax and bcl-xl and caspases3 may involve in the MNUinduced rat photoreceptor cell apoptosis.
Objective To investigate the relationship between surgical operation and hypophosphatemia, to observe the possible damage of hypophosphatemia and to assess the value of postoperative phosphate supplementation. Methods Sixty four male SD rats were randomly divided into 2 groups, Group Ⅰ, drinking a specially prepared solution to reduce their phosphate storage, Group Ⅱ, drinking water as a control. All received common bile duct ligation 3 weeks later. The serum biochemical data including phosphate level were obtained before and after operation. Then half of rats in each group were supplied with NaH2PO4 5-day survival rates were analyzed with statistic methods and their vital organs were observed under electron microscope. Results The phosphate level of each group was descended after operation. The group with phosphate shortage before operation (group Ⅰ) had a greatest fall of phosphate and average arterial pressure. The phosphate-supplied rats had a minor change of vital organs under electron microscope scan and higher 5-day survival rate compared to others in this group.Conclusion Abdominal surgery may induce postoperative hypophosphatemia, especially when the phosphate has been lacking before operation. Severe hypophosphatemia, superimposed on surgical trauma, enhances the damage to the body. Prompt supplement of phosphate will improve the prognosis of surgical operation.
Objective To observe the regulation effect of transforming growth factor alpha (TGFalpha;) on expression of glutamate transporter(GLAST)and ingestion activity of retinal Muuml;ller cells in mice. Methods To take the retinal tissue of Kunming mouse at postnatal 7~10 day, and then cultured Muuml;ller cells according to literature. The 3~4 generation cultured cells of the same primary cell were divided into two groups at random: ① TGFalpha; group: maintained in different concentrations of TGFalpha; as 50, 75, 125 and 150 ng/ml, 3 holes in each concentration;② Control group: cultured by Eagle culture medium which improved from Dulbeccon and contained 20% fetal calf serum. The influence of different concentrations TGFalpha; on GLAST activity in Muuml;ller cells were observed by L-3H-glutamate uptake detection; the expression of GLAST mRNA in Muuml;ller cells was determined by RT-PCR; the expression of GLAST protein was detected with immunocytochemical staining. Results With the increase of TGFalpha; concentration, both L3H glutamate uptake and GLAST mRNA expression were increased. The L-3H-glutamate accumulation had got to the maximum uptake at concentration of 125 ng/ml, which was 266% of that in control group, meanwhile, the expressions of GLAST mRNA also got to the maximum as 4 times of control group. Immunocytochemical staining indicated that the effect of 125ng/ml TGFalpha; on expression of GLAST protein was higher than that in the control group, the differences between two groups were statistically significant (Plt;0.05). Conclusion TGF-alpha; can increase GLAST activity through up-regulating the expression of GLAST mRNA and protein.
Objective To establish an rat model of the Anterior Isc hemic Optic Neuropathy (rAION), and identify its reliability by observing the fundus, fluorescein fundus angiography (FFA),optical coherence tomography (OCT), v isually evoked potential (VEP) and histopathology. Methods Thirty male Sprague-Dawley rats were randomly divided into group Naive with 5 rats, group Laser with 5 rats, group hematoporphyrin derivative(HPD) with 5 rats, group rAION with 15 rats. All of the right eyes were the experimental eyes and the left ones were the control. after administration of HPD in rats` vena caudalis. The rats in group Laser were treated with a krypton red 647nm/2/3disc spot laser for 120 seconds, the rats in group HPD were treated by administration of HPD in rats` vena caudalis, and the rats in group Na?ve were not treated. Results From 1 day to 6 day s after rAION induction, the ON was pale and swollen in the superior part. The ON at 90 days after induction was pale and shrunken.30 minutes after rAION induction, hyperfluoresc ence appeared in the superior part of the optic disc, and the hypofluorescence in the 23rd day. In early FFA, hypofluorescence appeared at the ischemic area of the optic disc, and in midst and later stage the ischemic area revealed hyperflu orescence in the 1st day after rAION induction, the hypofluorescence in midst and later stage in the sixth day after r-AION model. The latent period of F-VEP expanded. The amplitude cut down in the 1-2 days after r-AION induction and did not changed in 35nd day. The surface of optic disc showed higher and rougher tha n the surface of retina in the 6th day after r-AION induction in OCT. After fixation and hematoxylineosin staining of 6-mu;m sections, in high power field the o pt ic disc showed edema with the displacement of retina surrounding the disc 1 day after treatment. Rarefaction and degeneration in the nerve fiber of retina and r eduction of the number of nuclei of ganglion cells in the 23st day after the mod el induction, and the thinning of nerve fiber of the optic disc and its surround ings. In contrast, there was no change in group Na?ve, group Laser and group HPD. Conclusions The r-AION model is like the human AION in fundus, FFA, OCT, VEP and histopathology. The rAION model provides the ischemic changes of occurrence of AION, and is helpful for the fundamental study of the AION. (Chin J Ocul Fundus Dis,2008,24:90-94)
ObjectiveTo provide the reliable model in the rat for the study of liver transplantation.MethodsA surgical experience with one hundred and fifty orthotopic liver transplants in rats was reviewed,meanwhile a simple method with biliary extradrainage as well as bile collection was introduced.Results The operative successful rate was 93.8%(91/97),the survival rate after one week was 85.9%(55/64),the recipient underwent an anhepatic period of 19 min,the operative time of donor and recipient were 37 min and 56 min,respectively.ConclusionThe result indicates that the model is reliable in the study of liver transplantation.The hard work and meticulous surgical performance are the key to successful operation.
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.
Objective To further investigate pathologic mechanism of retinal phototrauma. Methods Twenty Wistar rats were divided into control and experimental groups.Their eyes were extracted in 12,24 and 36 hours after light exposure.HE stained retina samples were examined and TDT-mediated dUTP nick end labelling(TUNEL)method was employed to distinguish apoptotic cells. Results After 12-hour light exposure,slight vesiculation was observed in the rod outer segment of the retinas.After 24-hour light exposure,the outer nuclear layer showed predominant fractured and condensed nuclei and fragmented DNA.After 36-hour light exposure,the rod outer and inner segments were lysed and most of the nuclei in the outer nuclear layer were disappeared. Conclusions Apoptosis of photoreceptor cell is one of the important mechanisms which cause experimental retinal photoinjury of rats. (Chin J Ocul Fundus Dis, 1999, 15: 167-169)