RESULTS:1. HE staining pathological changes in brain cells of rats: the cells in CG neatly arranged was significantly. The brain cells in IH group for four weeks were damaged, cytoplasm sparse, boundaries unclear; while the cells for six weeks were disorganized, density decreased, quantity reduced. Four weeks of brain cells in HI group were neatly arranged basically, cells were relatively clear; as to six weeks cells were swelling, scarce cytoplasm, nuclear stained. 2. Compared with CG, in IH group the expressions of CaMKII and CB1 receptor in cerebral hippocampus were elevated, and with the duration of hypoxia, their expressions were more remarkable. 3. Compared with IH group, the HI group CB1 expression results were lower. 4. Correlation analysis: IH group expression levels of CaMKII and CB1 receptor were positively correlated significantly.