Abstract:
Objective:To explore the effect of venous hypertension on blood flow shear stress in the superior sagittal sinus of rats, and the effect and underlying mechanism of apoA-I binding protein (AIBP) mediated angiogenesis. Methods:Four rat models with different venous hypertension gradient were established. Group A had right carotid artery and external jugular vein anastomosis, occlusion of left transverse sinus vein, and craniectomy of parietal bone. Group B had right carotid artery and external jugular vein anastomosis and craniectomy of parietal bone. Group C had ligation of right carotid artery and right external jugular vein and craniectomy of parietal bone. Group D had craniectomy of parietal bone. The shear stress of superior sagittal sinus was measured and calculated after 3 months. The expression of AIBP and vascular endothelial growth factor (VEGF) in dura tissue was detected using Western blotting, real-time PCR, and immunohistochemistry. Human umbilical vein endothelial cells (HUVECs) were cultured under different shear stress. After 24 h, the expressions of AIBP, VEGF, and total cholesterol in the HUVECs were analyzed. Results:The shear stress of superior sagittal sinus in the rats with venous hypertension was greater than that in the Group D (P<0.05). The real-time PCR and Western blotting results showed that, compared to the Group D, the expression of AIBP decreased and VEGF increased in dura tissue of rats in Group A and B (P<0.01). Immunohistochemical results showed that AIBP expressed in the whole vascular layer. In HUVECs, the AIBP decreased, whereas the VEGF and total cholesterol increased significantly in the high shear stress group than those in the low shear stress group (P<0.05). Conclusions:Venous hypertension can increase shear stress in superior sagittal sinus. High shear stress may inhibit the expression of AIBP, reduce the cholesterol, and promote VEGF-mediated angiogenesis.