【摘要】 目的:探讨一种人工合成的纤维蛋白原降解肽片段RGDS对脓毒性休克大鼠心肌肌浆网钙转运功能的影响。方法:大鼠盲肠结扎穿孔术后4h和14h分两次尾静脉注射RGDS 5μmol·kg^-1。制备大鼠心肌肌浆网（SR）膜;测定SR Ca²⁺摄取和[³H]ryanodine受体结合功能。结果:RGDS组大鼠心肌SR摄Ca²⁺率及摄Ca²⁺量分别较休克组提高104％（P<0.01）和12％（P<0.05）,而心肌SR钙释放通道-[³H]ryanodine受体结合B_max和K_d值没有明显变化。同时RGDS还可以减轻休克大鼠心肌组织钙聚积。结论:RGDS提高休克大鼠心肌SR Ca²⁺摄取功能,维持心肌细胞钙稳态,具有心肌保护作用。更多还原

【Abstract】 AIM: To study the effects of Arg-Gly-Asp-Ser (RGDS), a synthetic short peptide of fibrinogen degradation, on the Ca2+ transport function of cardiac sarcoplasmic reticulum in rat septic shock. METHODS: RGDS 5 μmol·kg-1 was injected iv at 4 h and 14 h after cecal ligation and puncture (CLP) operation on rats. Highly purified membrane of sarcoplasmic reticulum (SR) was prepared from rat hearts. Assays were made of ATP-dependent Ca2 + uptake by cardiac SR and [3H]ryanodine binding to SR. RESULTS: The initial rate and the capacity of SR Ca2 + uptake were increased by 104 % (P<0.01) and 12 % (P< 0.05), respectively, paralleled by an increase in Ca2+ -ATPase activity and a decrease in calcium accumulation of myo- cardium of septic rats, whereas the Bmax and Kd values of Ca2+ activated [3 H]ryan-odine binding to SR were unaffected after RGDS administration. CONCLUTIONS: The results indicated that RGDS have cardioprotective effects of maintaining Ca2+ homeostasis of cardiac myocytes by enhancing SR Ca2+ uptake in rat septic shock.更多还原