摘要
目的 :观察瘦素对离体血管平滑肌收缩和舒张功能的影响 ,并探讨其机制 .方法 :采用离体血管灌流试验 ,测定血管平滑肌的张力改变 ;贴块法培养血管平滑肌细胞 (vascularsmoothmusclecell,VSMC) ,生化定磷法测定细胞内Na+ K+ ATPase活性的改变 .结果 :①瘦素对去甲肾上腺素 (nora drenaline,NE)引起的血管平滑肌收缩有明显促进作用 ,且明显延长其舒张时间 ;②瘦素抑制VSMC内Na+ K+ ATPase活性且有剂量和时间依赖性 ;③PI 3K抑制剂Wortmannin可抑制瘦素对VSMC的上述作用 .结论 :①瘦素对血管平滑肌舒缩功能的影响与其抑制VSMC内Na+ K+ ATPase活性 ,使细胞内 [Ca2 + ]i 升高有关 ;②瘦素对Na+ K+ ATPase活性的影响是经由受体后PI 3K信号通路实现的 .
AIM: To investigate the effects of leptin on the contraction and relaxation of isolated thoracic aortic smooth muscle and its mechanism. METHODS: Isolated thoracic aorta was perfused and the tension of the vessel was measured. The activity of Na +-K +-ATPase of vascular smooth muscle cells (VSMC) was measured by biochemical method. RESULTS: ① Leptin promoted the vasoconstriction induced by noradrenaline and prolonged the relaxation duration of isolated thoracic aorta. ② Leptin inhibited the activity of Na +-K +-ATPase. ③ Wortmannin inhibited the above effects of leptin on VSMC. CONCLUSION: ① The effect of leptin on contraction and relaxation of isolated vascular smooth muscle may be related to the intracellular change of the activity of Na +-K +-ATPase. ② Leptin affects the activity of Na +-K +-ATPase by intracellular PI-3K signal pathway.
出处
《第四军医大学学报》
CAS
北大核心
2004年第20期1846-1849,共4页
Journal of the Fourth Military Medical University
