Experimental Study On Delayed Cerebral Vasospasm (DCVS) Induced By The Subarachnoid Hemorrhage With Hypothermy

Delayed cerebral vasospasm (DCVS) induced by the subarachnoid hemorrhage is one of the major causes of patient's death and disability; however there is not very pleasant progress in its mechanism, process, hemodynamics, related biochemical index, mechanism in the molecular level and the therapy. It's need to further research.The experiment is aimed to find the mechanism of DCVS for further basic research and the clinical monitoring and healing.The test 1: The auther uses two injections of nonheparinized autologous arterial blood into the cisterna magna, which simulates cerebral vasospasm process induced by the subarachnoid hemorrhage, besides the author uses Laser Doppler Flowmetry (LDF) to monitor the cortical cerebral blood fluid (CBF), and microdialysis instruments to monitor the brain tissue metabolism in the fifth day after hemorrhage. The result indicated that both the LDF and the microdialysis instruments are excellent ways, and the hypothermy could improve the brain tissue metabolism status in some degree.The test 2: The author monitors the NOS energy and ET-1 concentration, and the result indicated that both ET-1 and NO are the critical substances in the process of the cerebral vasospasm. The monitoring of them could do a favor for the prognosis of the disease; beside the hypothermy could improve the NOS energy and reduce ET-1 concentration.The test 3: The author uses the RT-PCR techniques to observe genes expression status such as Bcl-2,Bax,iNOS,ET-1 in the brain tissue. The outcome indicated that there are changes in genes expression, which could explain the DCVS in aspect of the apoptosis. Beside the hypothermy could up regulate some apoptosis genes such as Bax,iNOS,ET-1, and down regulate some anti-apoptosis genes such as Bcl-2.This test is composed of three parts, which describe the cortical cerebral blood fluid, brain tissue metabolism status, biochemistry index in serum, and apoptosis genes changes in brain tissue. With the hypothermy therapy, it explain the DCVS mechanism in ways above. These provide some suggestions for further research and clinical works.