[The effect of ginkgolide B on astrocyte GFAP expression after the focal cerebral ischemia].

OBJECTIVE: To observe the effect of platelet activating factor (PAF) antagonist, ginkgolide B (GB), on the expression of glial fibrillary acidic protein (GFAP) in astrocytes during focal cerebral ischemia, of which the mechanism will be explored too. METHODS: The focal cerebral ischemia of tree shrews was induced to form via photochemical reaction. Morphological changes were observed by hematoxylin-eosin staining and electron microscopic technology. The GFAP expression in astrocytes was detected by immunohistochemistry. RESULTS: Morphological changes of the brain tissue occurred after focal cerebral ischemia. Astrocytes were more swollen with the prolongation of ischemia. The GFAP expression in astrocytes in the penumbra didn't change obviously at 4 h, but increased significantly at 24 h (P < 0.01), and retained the higher level at 72 h (P < 0.01) after focal cerebral ischemia. Whereas in contralateral cortex, the GFAP expression began to increase at 72 h (P < 0.05) after focal cerebral ischemia. With giving experimental animals GB at 6 h, the GFAP expression decreased until at 24 h after focal cerebral ischemia. CONCLUSION: GFAP expression in astrocytes increases after focal cerebral ischemia. And by inhibiting the astroglial GFAP expression, the ginkgolide B exerts the cerebral protective effects.