EXPERIMENTAL STUDY OF VARIATION IN BRAIN EDEMA AFTER THE FOCAL CEREBRAL ISCHEMIA IN RATS

To explore the dymamic vartion in brain edema after the focal cerebral ischemia, we determined changes of brain water content after middle cerebral artery. Twenty-eight normal SD rats(200~300g,female or male)were randomly divided into three groups:the normal group(n=4),the false operation group(n=4),and the ischemical injury group( n =20,each 4 of them were respectively observed at 2h,4h,8h,15h and 30h after MCAO). It was found that the water contents of brain tissues in normal group were similar to that in false operation group.In ischemical injury group,the contents were increasing from 2h after MCAO and reached a top value at 8h ( p 0 05), then gradually decreased( p 0 05). The brain tissue edema appears from 2h after MCAO and reaches the top at 8h and then gradually decreases.