BACKGROUND: When central nervous system is injured, re-expression of nestin protein may enhance the anti-injury ability of cells and be advantageous to the repair of focus of injury.OBJECTIVE: To explore the reaction of nerve stem cell (NSC) in permanent brain ischemia through NSC migration and the change of nestin protein expression.DESIGN: A randomized and controlled verification research with experimental animals as subjects.SETTING: Anatomy teaching and research offices in a training school and a university.MATERIALS: The experiment was done in the Teaching and Research Office of Humane Anatomy in Medical College of Xi'an Jiaotong University from October 1999 to January 2001. Totally 75 healthy SD rats were selected and randomly divided into normal control group, experiment group and sham-operation group. Twenty-five animals were in each group. Heads of animals were cut and brain was got out at the 1st, 3rd, 7th, 14th and 28thdays after operation, 5 animals at each time.METHODS: The model was rats with permanent cerebral ischemia. Immunohistochemical dyeing methods were used to observe NSC migration,change of marker of NSC and nestin protein at the 1st, 3rd, 7th, 14th and 28th day after cerebral ischemia.MAIN OUTCOME MEASURES: ①Results of immunohostochemicaldyeing. ②Migration length of nestin+ cells in anterior subentricular zone (SZa) region of brain tissue at normal status and at different time points after cerebral ischemia. ③Number variation of nestin+ cells at different timepoits after ischemia near the ischemic region.RESULTS: Through nestin immunohistochemical dyeing, it was found that NSC in normal brain tissue mainly existed in subependymal zone (SEZ)region. NSC of SEZ migrated in the direction of ischemic region along ventri- corpus callosum after ischemia. Among them, it reached the farthest at the 7th day after ischemia. More nestin+ cells appeared near ischemic region at the 1st day, and then reduced little by little 3 days later.CONCLUSION: NSC has certain reactive ability to ischemic brain injury.Expression of nestin protein near ischemic region may be a kind of protection to injury.

BACKGROUND: Neuroscience and brain science researches have paid attention to the effect of astragalus membranaceus in the treatment of neurologic impairment disease and neural regeneration. Studying astragalus membranaceus effects on neural stem cells are becoming a new research direction. OBJECTIVE: To explore the effects of astragalus injection on biological viability of rat neural stem cells. METHODS: Neural stem cells of Wistar rats were separated and cultured. Immunofluorescence staining was applied to identify the neural stem cells. The purified cells were gained by the second subcultivation in vitro, and then the cells were randomly divided into control group and astragalus injection groups with various concentrations (50, 200, 400 g/L) to culture for 6, 12 and 24 hours. The activity of cells was tested by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay, and then the immunohistochemistry was applied to detect the expressions of neuron-specific enolase and glial fibril ary acidic protein in the 50 g/L astragalus injection group after induced for 7 days. RESULTS AND CONCLUSION: The viability of neural stem cells increased significantly after intervention with different concentrations of astragalus injection for 6 hours as compared with the control group (P < 0.05). However, there was no difference in the cel viability after treated with different concentrations of astragalus injection for 24 hours (P > 0.05). Compared with the control group, the cells in the 50 g/L astragalus group differentiated rapidly, and the number of positive cells for neuron-specific enolase was increased significantly (P < 0.05). The neural stem cells proliferation was hastened, and its differentiation was promoted by the interference of astragalus injection.

AIM: To observe the change of TNF-? mRNA in hypertrophic cardiac myocytes induced by pressure overload in rats and the effect of captopril. METHODS: Serum and heart were collected 42 days after the cardiac hypertrophy model made by pressure overload by abdomen aorta-constriction (AC). Hypertrophic parameter and the concentration of TNF-? in serum and left ventricle were determined by ELISA. TNF-? mRNA in cardiac myocytes was determined by in situ hybridization and analyze by ELIA image analysis system. The orientation of (TNF-?) mRNA in cardiac myocytes was also observed. RESULTS: Left ventricle hypertrophy was observed 42 days after operation. TNF-? mRNA in AC group elevated 98% compared to sham-operated group and descended 64.14% by captopril ((P

This article analyzed the limitation of the traditional microcosmic teaching of morphology and the advantages of the interaction of the microscopic digital system applied in experimental teaching of morphology.