Experimental Study of Neural Stem Cells around the Lateral Ventricular Zone of the Hydrocephalus Rats
|School||Dalian Medical University|
|Keywords||Rats Hydrocephalus Animal models Neural stem cells|
Objective: To establish the communicating hydrocephalus rat model by the injection of kaolin to the cisterna magna and observe the changes of neural stem cells around the rats lateral ventricle. Discusses the pathophysiological process and repair mechanisms . Provide the theoretical basis for the treatment of communicating hydrocephalus though the new treatments and appropriate treatment time.Methods: 70 healthy 6 weeks Wistar rats were randomly divided into control and experimental group , each group have 35 rats. The 35 rats were randomly divided equally into 5 subgroups. for example: group A(3d)、B(1w)、C(2w)、D(3w) and E(4w). After rats anesthetized, We use micro-syringe needle occipitocervical fascia and immediately stop when there is a sense of frustration, colorless CSF was slowly sucked out of 0.05ml.Then, 250mg/ml 0.05ml sterile kaolin suspension was slowly injected into the cisterna magna .The eye of a needle was closed by the biological glue, Incision was sutured and maintain the head-down for 15-20 minutes. The same location in control rats were injected with sterile saline 0.05ml.The lateral ventricular width was measured by the MRI after 3 days, 1 week, 2 weeks, 3 weeks and 4 weeks. rats were perfused and fixed by the physiological saline and 4% paraformaldehyde at the same day. The brain was placed in 4% paraformaldehyde for 12 hours, after it was removed. Followed by 20%, 30% sucrose gradient dehydrated 1 day, until the brain completely sink to the bottom. After embeded by the OCT, the brain was frozen in liquid nitrogen surface for 20 seconds. and It was cut into 10 microns slices at - 30℃frozen section machine. Immunohistochemical staining method was applied, Nestin-positive cells distribution and changes were observed in rat periventricular.Results:In the experimental group, 28 rats were successfully induced hydrocephalus and complete the experiment, 30 rats in control group also completed the entire experiment. In the control group, the lateral ventricle have no significant expansion, P> 0.05. the difference was not statistically significant. But in the experimental group, the rats lateral ventricle expand with time, P<0.01. the difference have statistically significant. nestin-positive cells number: In the experimental group, the average number maintained 193±20.3. But in the experimental group, it reach the maximum (594±38.2) at 3 days and is the(308±1)% times to control group (P <0.001);After 1 week, the number decreased to the (196±1)% times to the control group; 2 weeks later, the number decreased to 210±22.4, P> 0.05; but 3 weeks later, we hardly see nestin-positive cells in the periventricular.Conclusions: It can establish the communicating hydrocephalus rat model by the injection of kaolin to the cisterna magna. and It can be used for the experimental study of hydrocephalus. the numbers of periventricular neural stem cells rapidly reached peak in the early and decreased gradually over time until it disappears. It can be considered that the ventricular mechanical expansion led to the ischemia and hypoxia of surrounding tissue, and the changes may have relation to it . Neural stem cells were involved in the changes of pathophysiology and the repair process of hydrocephalus.