目的:研究VEGF/VEGFR在脑缺血再灌注损伤中的神经保护作用。方法:SD大鼠108只,随机分为假手术组、对照组与VEGFR抗体组,每组36只,制备大脑中动脉缺血再灌注损伤(MCAO)模型,假手术组不造成缺血。VEGFR抗体组在造模前20 min侧脑室注射VEGF抗体,假手术组、对照组侧脑室注射等量生理盐水。比较3组在造模后1、3、7 d Bederson评分、VEGFR及缺血半暗带VEGFR2的变化。结果:VEGFR抗体组的Bederson评分在第1、3天高于对照组(P<0.05),VEGFR的表达在第1、3天低于对照组(P<0.01),但较假手术组高;VEGFR抗体组VEGFR2表达在第1、3天低于对照组(P<0.01)。结论:脑缺血再灌注损伤时,VEGF活化刺激VEGFR表达上调,促进血管内皮细胞增殖,加速新生血管形成。
Abnormal proliferation and migration of vascular smooth muscle cells(VSMCs) are the major cause of in-stent restenosis(ISR). Intervention proliferation and migration of VSMCs is an important strategy for antirestenotic therapy. Roscovitine, a second-generation cyclin-dependent kinase inhibitor, can inhibit cell cycle of multiple cell types. We studied the effects of roscovitine on cell cycle distribution, proliferation and migration of VSMCs in vitro by flow cytometry, Brd U incorporation and wound healing assay, respectively. Our results showed that roscovitine increased the proportion of G0/G1 phase cells after 12 h(69.57±3.65 vs. 92.50±1.68, P=0.000), 24 h(80.87±2.24 vs. 90.25±0.79, P=0.000) and 48 h(88.08±3.86 vs. 88.87±2.43, P=0.427) as compared with control group. Roscovitine inhibited proliferation and migration of VSMCs in a concentration-dependent way. With the increase of concentration, roscovitine showed increased capacity for growth and migration inhibition. Roscovitine(30 μmol/L) led to an almost complete VSMCs growth and migration arrest. Combined with its low toxicity and selective inhibition to ISR-VSMCs, roscovitine may be a potential drug in the treatment of vascular stenosis diseases and particularly useful in the prevention and treatment of ISR.
