Laser Speckle Imaging Combined With Photochemical Cerebral Ischemia Model And The Application In Novel Drug Evaluation

Object:The laser speckle imaging is a new blood flow imaging technique in vivo. This research is to find potential application of the laser speckle imaging in collateral circulation and photochemical cerebral ischemical model, investigate the relationship of the blood flow change and lesion pathology, test the effect of durgs for cerebral ischemic disease.Method:Cerebral blood flow in C57/BL6mice and collateral circulation was observed by laser speckle imaging after unilateral carotid artery ligation. Mouse cerebral ischemia model was produced by photochemical methods to analyze the changes in cerebral ischemia regional blood flow signals. The relationship between the volume of cerebral infarction and the number of small blood vessels in ischemic area was caculated. The changes in small blood vessels, glial cells and neurons was. indentified with pathological methods. Laser speckle imaging was performed to test the effect of urinarykallid, minocycline, dexamethasone in the cerebral ischemia model.Result:Laser speckle imaging C57mice were suitable to detect dynamically cerebral blood flow. C57mice after cerebral ischemia photochemical modeling could be repeatedly checked. The correlation coefficient R2between ischemic tissue volume and normalized SrCBF is0.9001. The pathology showed Neun positive cells in ischemic area at1d. Little Brdu and Neun positive cells could found in the ischemic edge at28d. Astrocytes activation by GFAP staining can be found in the edge of ischemic lesions, with5d peaked activation. After surgery, SrCBF and ischemic tissue volume in the minocycline group can be found statistical difference compared with the control group at3d.Conclusion:Laser speckle imaging system could real-time display the dynamic changes in cerebral blood flow, which provides a good research tool for the small cortical vascular function and collateral circulation associated with cerebral ischemia in mice. Photochemical modeling with different doses can produce varying degrees of infarct for different types of research experiments. The blood flow index SrCBF could reflect the degree of photochemical ischemic tissue volumes, indicating the number of local small blood vessels. The relationship between the small blood vessels and nerve cells, glial cells was still tight in photochemical models of cerebral ischemia. Laser speckle imaging combining C57/BL6mice photochemical cerebral ischemia model has be considered as a stabilized tool for ischemic research. Minocycline and other vascular protective durgs may benefit the ischemic stroke.