异丙酚对中性粒细胞活性氧生成及细胞内游离Ca^(2+)浓度的影响

Effects of Propofol on the Production of Active Oxygen Species and Concentration of Intracellular Ca^(2+) in Neutrophils

目的 :测定异丙酚对中性粒细胞 (PMN)激活后活性氧生成以及细胞内游离Ca2 + 浓度 ([Ca2 + ]i)的影响 ,探讨异丙酚影响PMN呼吸爆发的内在机制。方法 :利用电子自旋共振 (ESR)技术和自旋捕捉法 ,观察异丙酚对PMN呼吸爆发产生氧自由基 (ROS)的抑制作用 ;同时采用钙荧光指示剂 (Fura 2 /AM)负载离体PMN并行双波长模式测定不同浓度异丙酚对静息和激活状态下PMN细胞内 [Ca2 + ]i 的影响。结果 :高浓度 (75 μM)异丙酚可使静息状态下PMN细胞内 [Ca2 + ]i升高 ;在有钙基质中 ,异丙酚对趋化三肽 (fMLP)诱发的PMN胞内 [Ca2 + ]i 的升高有明显的降调作用 ,而在无钙基质中则不明显。在无钙基质中 ,高浓度 (≥ 5 0 μM )的异丙酚对fMLP诱发PMN呼吸爆发产生ROS有明显的抑制作用 ;而存在胞外钙浓度时 ,2 5 μM异丙酚的抑制程度更为明显。结论 :异丙酚可通过作用于胞外钙内流和胞内储存钙释放影响静息及激活状态下PMN胞内 [Ca2 + ]i;异丙酚在有钙基质中对PMN呼吸爆发产生ROS的抑制作用更为明显 ,提示异丙酚影响PMN胞内 [Ca2 + ]i,特别是对胞外钙内流的抑制作用 ,可能是其抑制PMN呼吸爆发的内在机制之一。

Objective: The effects of propofol on the production of active oxygen species and intracellular Ca 2+ ([Ca 2+ ] i ) in polymorphonuclear neutrophils(PMN) were studied to elucidate their relationship and the mechanism.Methods:Directly observing the effects of propofol on the production of active oxygen species of PMN with electron spin resonance and spin trapping was carried out and the effect of propofol on [Ca 2+ ] i in activated or inactiated PMN was also measured with doublewavelength mode using fluorescent intracellular probe fura2.Results:High concentration(75μM)of propofol could increase [Ca 2+ ] i in inactivated PMN.In activated PMN,under [Ca 2+ ] ocontaining condition,propofol downregulated [Ca 2+ ] i in PMN activated by fMLP,but it was not seen under [Ca 2+ ] odepleted condition.Under [Ca 2+ ] odepleted condition,propofol(≥50μM) inhibited the production of active oxygen species in activated PMN and under [Ca 2+ ] ocontaining condition,only 25μM of propofol was needed and its inhibition was more significant.Conclusion:Propofol can regulate [Ca 2+ ] i in activated or inactivated PMN by affecting both Ca 2+ influx and releasing from intracellular storage sites.Under [Ca 2+ ] ocontaining condition,propofol is more effective in inhibiting the respiratory burst of PMN due to the effects of propofol on [Ca 2+ ] i,especially the inhibition of Ca 2+ influx.