Tuomala M, Hirvonen M R, Holopainen M, Savolainen K
National Public Health Institute, Department of Toxicology, Kuopio, Finland.
Toxicol Appl Pharmacol. 1993 Feb;118(2):224-32. doi: 10.1006/taap.1993.1028.
The role of free intracellular calcium [Ca2+]i was studied in the production of reactive oxygen metabolites (ROM) by human polymorphonuclear leukocytes (PMNL) after a single or two repeated doses of quartz. The significance of [Ca2+]i in the production of ROM was also studied after a dose of quartz prior to, or after, a dose of formylmethionylleucylphenylalanine (fMLP). When the production of ROM and changes in [Ca2+]i were measured after repeated stimulations of cells, the cells were always washed between stimulations. A dose of quartz elevated [Ca2+]i in untreated and washed cells, whereas a second dose of quartz did not induce any further increase in [Ca2+]i. On the contrary, quartz stimulated ROM production after both one and two consecutive doses. fMLP alone elevated [Ca2+]i and increased the production of ROM. Quartz before fMLP did not modify fMLP-induced [Ca2+]i increase, but attenuated fMLP-induced ROM production. Quartz-induced elevation of [Ca2+]i was not affected by a prior dose of fMLP, but the production of ROM by quartz was greatly amplified by prior exposure of PMNL to fMLP. Thus, both quartz and fMLP increase the production of ROM by mechanisms in which [Ca2+]i may have a key role. Priming of PMNL with fMLP prior to quartz seems to amplify quartz-induced ROM production but not to affect [Ca2+]i. It is plausible that both [Ca2+]i-dependent and -independent mechanisms may account for quartz-induced ROM production in PMNL.
研究了单次或两次重复剂量石英刺激后人多形核白细胞（PMNL）中游离细胞内钙[Ca2+]i在活性氧代谢产物（ROM）产生中的作用。还研究了在给予甲酰甲硫氨酰亮氨酰苯丙氨酸（fMLP）剂量之前或之后给予石英剂量时，[Ca2+]i在ROM产生中的意义。当在细胞重复刺激后测量ROM产生和[Ca2+]i变化时，每次刺激之间总是对细胞进行洗涤。一剂石英可使未处理和洗涤后的细胞中[Ca2+]i升高，而第二剂石英并未引起[Ca2+]i的进一步增加。相反，连续一剂和两剂石英均刺激了ROM的产生。单独的fMLP可升高[Ca2+]i并增加ROM的产生。fMLP之前的石英不会改变fMLP诱导的[Ca2+]i增加，但会减弱fMLP诱导的ROM产生。石英诱导的[Ca2+]i升高不受先前剂量fMLP的影响，但PMNL预先暴露于fMLP可极大地放大石英诱导的ROM产生。因此，石英和fMLP均通过[Ca2+]i可能起关键作用的机制增加ROM的产生。在石英之前用fMLP预处理PMNL似乎可放大石英诱导的ROM产生，但不影响[Ca2+]i。Ca2+依赖和非依赖机制都可能解释PMNL中石英诱导的ROM产生，这似乎是合理的。
