小鼠腹腔巨噬细胞基态游离钙离子浓度的不均一性及其和细胞反应性的关系

目的:在单细胞水平上研究小鼠腹腔巨噬细胞(PM)基态游离钙离子浓度(Ca²⁺]_i)的不均一性及其和细胞反应性的关系。方法:用荧光指示剂Fura-2/AM结合荧光显微镜成像系统检测单个PM基态的及用激动剂刺激细胞后的Ca²⁺]_i;同时结合NBT染色法定量检测单个PM产超氧阴离子(O₂^-)水平。结果:对7只正常小鼠共392个PM基态Ca²⁺]_i的研究表明小鼠PM的基态Ca²⁺]_i呈正态分布(54±24)nmol/L,n=392],但波动范围较大(从10nmol/L到高于100nmol/L),以Ca²⁺]_i在40-60nmol/L的细胞数量最多(约占50%)。用PMA、fMLP刺激后PMCa²⁺]_i升高,且受刺激后Ca²⁺]_i升高的峰值和基态Ca²⁺]_i之间呈正相关(PMA刺激组:r=052,P<0.01,n=58;fMLP刺激组:r=0.59,P<0.01,n=44。此两组实验均以不同的小鼠重复3次,其它两只小鼠的结果与上同。下面的表述方法同此)。另外小鼠PM的基态Ca²⁺]_i与其受PMA刺激后产生O₂^-的量也呈显著正相关(r=0.42,P<0.01,n=43,重复4次)。结论:小鼠PM的基态Ca²⁺]_i是不均一的,且基态Ca²⁺]_i的高低和该细胞对致炎因子的反应性密切相关。

Heterogeneity of basal intracellular calcium concentration and its relations to the reactivity in mouse peritoneal macrophages

AIM: To investigate the heterogeneity of basal intracellular free calcium concentration(Ca²⁺]_i) in peritoneal macrophages(PM) and whether it is relative to the reactivity of PM at the single cell level. METHODS:Ca²⁺]_iimplicated stimulated were measured by fluorescent microscopic imaging system after loading with fluorescent probe fura-2/AM. Superoxide(O₂^-)produced by single PM was determined by modified NBT test. RESULTS: The values of basalCa²⁺]_idetermined in 392 PMs of 7 mice showed normal distribution (54±24) nmol/L, n=392] with wide range(less than 20 nmol/L to more than 100 nmol/L), among which about 50% were in the range of 40-60 nmol/L. When stimulated with PMA or fMLP,Ca²⁺]_iwas increased, the peak values were positively correlated with the basalCa²⁺]_iin one mouse(PMA stimulated cells: r=0.52, P<0.01, n=58; fMLP stimulated cells:r=0.59, P<0.01, n=44. Both of the experiments were repeated in 3 mice, the results in the other 2 mice were similar). The O₂^- in PMA stimulated PMs were also positively correlated with the basal i(r=0.42, P<0.01, n=43, repeated in 4 mice, the results in the other 3 mice were similar). CONCLUSION: BasalCa²⁺]_iin murine PM is heterogeneous, and the value of basalCa²⁺]_iis tightly correlated to the reactivity of PM stimulated by proinflammatory factors.