关键词: 慢性脑血流低灌注, 血-脑脊液屏障, 周细胞, 纤维蛋白原

Abstract: Objective To investigate the effect of chronic cerebral hypoperfusion (CCH) on the blood-brain barrier (BBB) and pericytes. Methods Bilateral common carotid artery ligation (2-VO) rat model was used. Cerebral blood flow (CBF) was measured at the 3rd, 14th and 30th day after 2-VO surgery. Pericyte and fibrinogen expression were detected by fluorescence immunohistochemistry. Primary cultured pericytes were subjected to cell proliferation experiments. Transmission electron microscopy was used to observe the ultrastructure of blood-brain barrier. Results CBF was decreased in each model group, and kept lower at 30th day after 2-VO. BBB was damaged with fibrin(ogen) extravascular leakage, thickening of the basement membrane, dense deposit in the extravascular space, astrocyte edema, and red blood cell extravascular leakage. The number of pericytes was increased on the 3rd, 14th, and 30th day after surgery. In vitro, low concentration of fibrinogen could promote the proliferation of pericytes, while high concentration (20mg/mL) of fibrinogen had toxic effects on the pericytes. Conclusion CCH disrupts the BBB accompanying with pericytes proliferation, and fibrinogen exudation may be the main cause of pericyte hyperplasia.

Key words: chronic cerebral hypoperfusion, blood-brain barrier, pericyte, fibrinogen