Yamamoto M, Okimasu E, Terada S, Utsumi K
Cell Struct Funct. 1987 Aug;12(4):357-67. doi: 10.1247/csf.12.357.
The stimulative effects of myristate on the superoxide generation and depolarization of membrane potential of polymorphonuclear leukocytes (PMN) are particularly strong, yet myristate does not affect the intracellular free Ca2+ level ([Ca2+]i) in the presence of 1 microM free calcium in calcium-EGTA buffer. The half maximum concentration of myristate was 10 microM. Myristate inhibited the transitory changes in [Ca2+]i induced by formylmethionyl-leucyl-phenylalanine (FMLP), but stimulated further the FMLP-induced superoxide generation; these effects are similar to those of phorbol myristate acetate (PMA). The myristate-induced superoxide generation was partially inhibited by H-7, a specific inhibitor of protein kinase C. Myristate stimulated the activity of Ca2+- and phospholipid-dependent protein kinase (protein kinase C) in a concentration-dependent manner in the presence of 10(-6) M Ca2+. The Ka was 100 microM. These results suggested that there is no relation between the superoxide generation and the [Ca2+]i change in PMNs and that the effects of myristate are similar to those of PMA against PMN.
肉豆蔻酸盐对多形核白细胞（PMN）超氧化物生成及膜电位去极化的刺激作用尤为强烈，然而在钙-乙二醇双乙酸盐缓冲液中存在1微摩尔游离钙的情况下，肉豆蔻酸盐并不影响细胞内游离钙离子水平（[Ca2+]i）。肉豆蔻酸盐的半数最大浓度为10微摩尔。肉豆蔻酸盐抑制了甲酰甲硫氨酰-亮氨酰-苯丙氨酸（FMLP）诱导的[Ca2+]i瞬时变化，但进一步刺激了FMLP诱导的超氧化物生成；这些效应与佛波酯肉豆蔻酸酯乙酸盐（PMA）的效应相似。肉豆蔻酸盐诱导的超氧化物生成被蛋白激酶C的特异性抑制剂H-7部分抑制。在存在10^(-6) M钙离子的情况下，肉豆蔻酸盐以浓度依赖的方式刺激了钙离子和磷脂依赖性蛋白激酶（蛋白激酶C）的活性。其解离常数（Ka）为100微摩尔。这些结果表明，PMN中超氧化物生成与[Ca2+]i变化之间不存在关联，且肉豆蔻酸盐对PMN的作用与PMA相似。
