ObjectiveTo observe the dynamic changes of neuroglobin (NGB) expression in hippocampus after status epilepticus(SE) in rats, and to explore the role of NGB in epileptic seizures.Methods40 healthy male Sprague Dawley rats were randomly divided into two group according to random number table method:control group (n=5) and epilepsy model group(n=35).Epilepsy model group according to observation time was divided into:0h, 1h, 3h, 12h, 24h, 10d and 30d.Intraperitoneal injection Lithium-pilocarpine (20 mg/kg~127 mg/kg, Li-PC) to establish the rat model of SE.Observe the behavioral changes in rats with epilepsy.Nissl staining was used to detect the neuronal damage in hippocampus. Streptavidin-biotin-peroxidase complex immunohistochemical method was used to detect the expression level of NGB in hippocampus;ResultsAfter SE, the neurons in hippocampus were severely damaged with the progress of epileptic seizures, the number of surviving neurons in CA1, CA3 regions showed a near linear decline.Among them, the number of surviving neurons in (12h, 24h, 10d, 30d)CA1, (0h, 12h, 24h, 10d, 30d)CA3 and(12h, 24h, 10d, 30d) DG area were significantly lower than that of the control group (P < 0.05).The expression level of NGB in CA1, CA3 and DG region of hippocampus were increased after SE, and both of CA1 and DG were reached peak in 24h after SE, but was still higher than the control group.And the CA3 area showed a continue rising trend.Among them, CA1(24h, 10d, 30d), CA3(24h, 10d, 30d) and DG(12h, 24h, 10d, 30d) were higher than that of control group significantly (P < 0.05).In addition, it was found that there was a positive correlation between the number of surviving neurons in CA3 area and the expression level of NGB (R=0.306, P=0.011).ConclusionUp-regulation of NGB expression in hippocampus after status epilepticus, and was positively correlated with the number of neurons in the CA3 area, suggesting that up regulation of NGB expression may be a compensatory protective mechanism of ischemic injury induced by seizures, and participate in the protection of epilepsy related neuronal damage.
Objective To observe the release pattern of the microcysts and the effect of ectopic osteogenesis of combined micromorselized bone by optimized preparation of microcysts. Methods Optimized poly-DLlactide-co-glycolide (PLGA) microcysts manufacturing method was performed with the orthogonal design, and the accumulated release amount of microcysts was calculated at 2 h, 4 h, 8 h, 12 h, 24 h, 36 h, 48 h, 60 h, 72 h, 84 h, 96 h, 120 h, 144 h, 168 h, 192 h, 216 h, 240 h and 264 h. Twentyfour Wistar rats were divided into 4 groups (n=6) and 1 cm length incision was cut in their bilateral thighs skin, forming 48 gluteus maximus muscle sackmodels. In group A,collagen was implanted to bilateral muscle sacks respectively. In group B, collagen and autologous morselized bone were implanted to bilateral muscle sacks. Ingroup C, collagen and rhBMP-2/PLGA delayed release microcysts were implanted to bilateralmuscle sacks respectively. In group D, collagen and morselized bone/rhBMP-2/PLGA delayed release microcysts were implanted to bilateral muscle sacks. Gross and histologic observations were made at 3, 4 and 5 weeks postoperatively.Results Every optimized variance had an effect on particle diameter of microcyst and its encapsulating rate. The microcyst’s surface was smooth and had a fine spheroplast, which released slowly within 11 days in vitro. In thethird week postoperatively, the graft in group A could not be touched, while the graft in all other 3 groups was still found. After 3 weeks, collagen was absorbed completely in group A, the residual collagen could be seen in groups B, C andD. After 4 weeks, collagen could be seen in group A; micromorselized bone continued to be absorbed and became smaller in group B; microsphere became smaller, osteoblasts increased in group C; micromorselized bone and microsphere continuedto be absorbed, oteoblasts and chondroblasts increased. After 5 weeks, implantsbecame small, microsphere was absorbed, osteoblasts and chondroblasts became more in groups B, C and D. Microcysts presented with white granuloshape and were packaged in tissue pieces. Histologic observation showed that the PLGA microcysts in 3 weeks and 4 weeks could be absorbed gradually as the time in vivo, if combining with morselzed bone they could produce abundant induced osteoblasts and chondroblasts. Conclusion Optimizing the preparation technology of microcysts has delayed their release during a long period in vitro. Autologous micromorselized bone can be ectopicly induced to produce large amount of osteoblasts in gluteus maximus muscle sack, where PLGA microcysts can combine organically and bring about the bone formation with less amount of growth factors.
Objective Bone marrow mesenchymal stem cells (BMSCs) play an important role in repairing nerve injury, meanwhile external temperature has significant effect on BMSCs transplantation, prol iferation, and differentiation. To investigate the effect of BMSCs transplantation and mild hypothermia on repair of rat spinal cord injury (SCI). Methods Forty-five female adult SD rats (weighing 200-250 g) were made the models of hemitransection SCI and divided randomly into 3 groups according to different treatments: group A (SCI group), group B (BMSCs transplantation group), and group C [BMSCs transplantation combined with mild hypothermia (33-35 ) group]. At 1, 2, 4, 6, and 8 weeks after injury, the fuction of hind l imb was evaluated with Basso Beattie and Bresnahan (BBB) score and incl ined plane test. At 4 weeks after injury, histopathology and BrdU immunohistochemistry staining were performed. At 8 weeks after injury, horseradishperoxidase (HRP) retrograde nerve trace and transmission electron microscope (TEM) testing were performed to observe the regeneration of axon. Results After 4 weeks, the function of hind l imb obviously recovered in groups B and C, there were significant differences in BBB score between groups B, C and group A (P lt; 0.05), between group B and group C (P lt; 0.05). There was no significant difference (P gt; 0.05) in tilt angle among 3 groups after 1 and 2 weeks, and there were significant differences (P lt; 0.05) among 3 groups after 4 weeks. HE staining showed that significant cavity could be seen in group A, l ittle in group B, and no cavity in group C. BrdU immunohistochemistry staining showed that the number of positive cells was 0, 90.54 ± 6.23, and 121.22 ± 7.54 in groups A, B, and C, respectively; showing significant differences (P lt; 0.01) among 3 groups. HRP retrograde neural tracing observation showed that the number of HRP positive nerve fibers was 10.35 ± 1.72, 43.25 ± 2.65, and 84.37 ± 4.59 in groups A, B, and C, respectively, showing significant differences (P lt; 0.01) among 3 groups. TEM observation showed that a great amount of unmyel inated nerve fibers and myel inated nerve fibers were found in central transverse plane in group C. Conclusion The BMSCs transplantation play an impontant role in promotion of recovering the function of hind l imb after SCI, and mild hypothermia has synergism effects.
ObjectiveTo investigate the behavioral recovery of spinal cord injury (SCI) rats that received transplantation of NEP1-40 gene-modified neural stem cells. MethodsNeural stem cells (NSCs) were derived from the cortex tissue of rat embryo at the age of 18 days and identified by Nestin immunofluorescence. The lentiviruses were transduced to NSCs to construct NEP1-40 gene modified NSCs. Spinal cords of 30 Sprague-Dawley rats were hemisected at the nineth thoracic vertebrae level. The rats were randomly assigned to three groups. Cell culture medium, NSCs and NEP1-40 gene-modified NSCs were transplanted into the lesion site of rats of SCI group, NSCs group and NEP1-40-NSCs group respectively 7 days after injury. Additional 10 rats served as blank control group (sham group), which only received laminectomy. Following transplantation, behavior tests including Basso, Beattie, Bresnahan (BBB) Locomotor Rating Scale and grid test were utilized to evaluate spinal cord functional recovery. ResultsBehavior tests 8 weeks after cells transplantation showed that the rats in SCI group got worst results, the BBB scores improved and the grid drop times reduced significantly in NSCs transplantation group (P<0.01) and behavioral test outcomes were best in the NEP1-40 gene-modified NSCs group (P<0.01). ConclusionNEP1-40 gene modification can significantly improve the behavioral recovery of SCI rats that received transplantation of pure neural stem cells. It can provide a new idea and reliable experimental base for the study of NSCs transplantation for spinal cord injury.
Objective To study the relationship between the expression ratio of induced nitric oxide synthase (iNOS) over glial fibrillary acidic protein (GFAP) and the time of injury after brain concussion in rat, in order to acquire a new visual angle for determining injury time of cerebral concussion. Methods Eighty-five healthy Sprague-Dawley rats were divided into three groups randomly: model group (n=25), experimental group (n=55), and control group (n=5). The rats in the model group were used to confirm the attack hight to make the model of brain concussion; according to the time of execution, rats in the experimental group were then subdivided into 11 groups with 5 rats in each subgroup, and their execution time was respectively hour 0.5, 1, 3, 6, 12, 24, 48, 96, 168, 240, and 336; the rats in the control group were executed after fed for 24 hours. After the model of cerebral concussion was established through freefalling dart method, hematoxylin-eosin staining and immunohistochemistry staining of iNOS and GFAP were conducted for the brain of the rats. All related experimental results were studied by using microscope with image analytical system and homologous statistics. Results The ratio of positive expression of iNOS over that of GFAP increased gradually during hour 0.5- 3 after injury in brain (from 5.03 to 10.47). At the same time, the positive expression of iNOS increased significantly (from 14.61% to 37.45%). However, the increase of the positive expression of GFAP was not obvious. Between hour 3 and 12, the ratio began to decline to 4.98, which was still at a high level, and during the same time period, the positive expressions of iNOS and GFAP also experienced the same change pattern. Later, the ratio began to decline between hour 12 and 336 after injury (from 4.98 to 0.95). All ratios at this time were lower than those between hour 0.5 and 12. The positive expression of iNOS and GFAP both increased to a climax before declining. Conclusions The ratio of positive expression of iNOS over GFAP and the respective change pattern of iNOS and GFAP can be used as the evidence of estimating the injury time of cerebral concussion. We can use the ratio of two or more markers to provide a new visual angle for concluding the concussion injury time.
Objective To study the relationship between the expression ratio of heat shock protein (HSP) 70 to C-fos in organs outside the brain after brain concussion and the time of injury in rats, in order to provide a new visual angle for determining injury time of brain concussion. Methods The model of brain concussion was established through free falling method. Then the rats were executed at 30 minutes, 1 hour, and 3, 6, 12, 24, 48, 96, 168, 240, 336 hours after injury. Immunohistochemistry staining of C-fos and HSP70 were used in the materials from the main organs including heart, liver, spleen, lung and kidney. All related experiment results were studied by using a microscope with image analytical system and homologous statistics. Results From 30 minutes to 6 hours after injury, the proportion of HSP70 immuno-positive cells increased slowly, while the proportion of C-fos immuno-positive cells increased rapidly, and the ratio of HSP70/C-fos positive cells was on the decline. From 6 to 12 hours after injury, the proportion of HSP70 immuno-positive cells rose continuously, while the proportion of C-fos immuno-positive cells started to decrease, and the HSP70/C-fos ratio showed a rising tendency. From 12 to 336 hours after injury, the proportion of HSP70 immuno-positive cells decreased slowly, while the proportion of C-fos immuno-positive cells decreased rapidly, and the HSP70/C-fos ratio was still on the rise. Conclusions The proportion of positive cells and ratio of the two markers in the main organs including heart, liver, spleen, lung and kidney are similar to those in the brain of rats after brain concussion. Observing the proportion of positive cells of the two markers together with their ratio in the main organs outside the brain may provide a reference for the determination of injury time after brain concussion.
【Abstract】ObjectiveTo investigate the effects of liver transplantation on splenic function in rats with hepatic cirrhosis. MethodsHepatic cirrhosis model was established in rats by subcutaneous injections of carbon tetrachloride. Liver transplantation model was established with twocuff technique. Spleen index, morphological changes of spleen were observed before and after liver transplantation in hepatic cirrhosis rats. Spleen T lymphocyte subgroups before and after liver transplantation were also assayed by immunofluorescence staining and flow cytometry. ResultsBefore liver transplantation, spleen index was increased from (2.42±0.11) mg/g to (3.62±0.14) mg/g， P＜0.01; pathological examination of spleen samples showed that the areas of white pulp were decreased from (23.47±2.30)% to (7.70±2.01)%， P＜0.01， and the areas of spleen trabecula were increased from (1.75±0.61)% to (4.46±0.71)%， P＜0.01. Meanwhile, the ratio of CD4/CD8 of spleen T lymphocyte subgroups was decreased from 2.67±0.15 to 1.18±0.15, P＜0.01. After liver transplantation, spleen index was decreased from (3.62±0.14) mg/g to (2.62±0.11) mg/g， P＜0.01; pathological examination of spleen showed that the areas of white pulp were increased from (7.70±2.01)% to (15.07±1.97)%， P＜0.01, and those of spleen trabecula were decreased from (4.46±0.71)% to (3.11±0.51)%， P＜0.05. Meanwhile, the ratio of CD4/CD8 of spleen T lymphocyte subgroups was increased from 1.18±0.15 to 2.32±0.11, P＜0.01. ConclusionImpaired function of spleen resulting from liver function damage can be improved in rats with hepatic cirrhosis after liver transplantation.
ObjectiveTo explore the mechanism of lung injury in Sprague-Dawley (SD) rats induced by acute organic phosphorus pesticides (AOPP) by observing the changes of the blood serum nuclear factor (NF)-κB consistence, NF-κB level of lung tissue and lung coefficient. MethodNinety-six healthy male SD rats (six weeks old) were randomly divided into group A (control, n=48) and group B (poison, n=48). The rats of group B were given omethoate by gavage (45 mg/kg), and the rats of group A accepted normal saline. Then the rats were killed at designated observing points (30 minutes; 3, 6, 12, 24, and 48 hours), and the lung coefficient, blood serum NF-κB consistence and NF-κB level of lung tissue were measured. At the same time, we observed the pathological changes of the rats' lung tissue. ResultsCompared with group A, blood serum NF-κB consistence, NF-κB level of lung tissue and the level of lung coefficient in group B were significantly higher (P<0.01). The lung tissues of group A were normal at each time point, but in group B, the lung pathological changes gradually appeared 30 minutes later with pulmonary interstitial engorging, alveolar septum widening and some alveolus being full of red blood cells, and this situation reached its peak at hour 12. Then it gradually mitigated from 24 to 48 hours. ConclusionThere are significant increases in blood serum NF-κB consistence and NF-κB level in lung tissues in rats with lung injury induced by omethoate poisoning. The NF-κB may play a role in the process of lung injury induced by organophosphorus pesticide.
Objective To explore the effects of several immunosuppressants on the cell numbers of cultured rat macrophages and Schwann’s cells. Methods The macrophages and Schwann’s cells were cultured from the newborn Wistar rats. Different concentrations of methylprednisolone(10-3, 10－4,10－6 and 10－8 mol/L), CsA(10－5, 10－6, 10－7 and 10－8 mol/L) and FK506(10-6, 10－7, 10－8 and 10－9 mol/L) were administrated to the cells, while control group was given no drugs. Twentyfour, 48 and 72 hours after administration, the cells from different concentrations were measured with MTT methods respectively. Theresults were compared and analyzed statistically. Results Only high concentration methylprednisolone (10-4 mol/L) and a certain range of concentrations of CsA (10-6，10-7 and 10-8 mol/L) and FK506 (10-7,10-8 and 10-9 mol/L) can provide protection to culturedrat macrophages. Under most concentrations, CsA and FK506 had no effects onthe cell number of cultured rat Schwann’s cell. Only with high concentration CsA (10-5 mol/L) and methylprednisolone (10-3 mol/L) could significantly decreased the cell number of Schwann’s cell. Long time (72 hours) and low dosage (10-8 mol/L) administration of methylprednisolone could significantlyprotect Schwann’s cell. Conclusion High concentration methylprednisolone and some certain concentration CsA and FK506 can protect cultured rat macrophages. But high concentration CsA and methylprednisolone prohibit the proliferation of Schwann’s cells. Only long time and low dosage methylprednisolonecan protect cultured rat Schwann’s cells.
Objective To investigate the effects of ectomesenchymalstem cells on hematopoiesis after total body irradiation in rats. Methods The primary ectomesenchymal stem cells were isolated from E11.5 SD fetal mandibular processes by 25g/L trypsin and cultured with DMEM/F12. The morphology and growthrate were observed by inverted microscope. Eighty SD male rats randomly dividedinto ectomesenchymal stem cells group (n=20), fibroblast group(n=20), saline group(n=20) and control group(n=20), the first three groups were irradiated with 60Co γ rays at 6.0 Gy. The number of their bone marrow nucleated cells was counted after 4 weeks; the forming ability of colony-forming unit-granulocyte macrophage(CFU-GM) and histopathology of bone marrow were also observed. Results The cultured cells displayed monolayer growth and fibroblast-like with 2-4 processes. The ectomesenchymal stem cells could increase the number of bone marrow nucleated cells and peripheral blood white cell count, and improve the forming ability of CFU-GM. After 4 weeks of transplantation, the number of the peripheral blood white cells in group A was more than that in groups B and C(Plt;0.05), the contents of Hb in groups A and D was significantly higher than those in groups B and C(Plt;0.0). After 4 weeks, the bone morrow nucleated cells in group A were significant more than those in groups B and C(Plt;001); CFU-GM in groups A and D was higher than that in groups B and C(Plt;0.01). Conclusion Ectomesenchymal stem cells have characteristics of stem cells. It may improve hematopoiesis recovery of irradiated rats.