Davies M P, Hallam T J, Merritt J E
Department of Cellular Pharmacology, Smith, Kline & French Research Ltd., Welwyn, Herts, U.K.
Biochem J. 1990 Apr 1;267(1):13-6. doi: 10.1042/bj2670013.
Stimulated adherence of human neutrophils to plastic and changes in cytosolic free Ca2+ concn. [( Ca2+]i) were measured in the same cell preparations. [Ca2+]i-activation curves were constructed to compare the relation between [Ca2+]i and adhesion in response to ionomycin and formylmethionyl-leucyl-phenylalanine (FMLP). This showed that FMLP-stimulated adhesion required less increase in [Ca2+]i than did ionomycin's effect, a result suggesting that an additional stimulatory component might be involved in the response to FMLP. Protein kinase C activation was a possibility, and activation of protein kinase C with a phorbol ester (PMA) was found to stimulate adhesion with no change in [Ca2+]i. A low concentration of PMA was found to synergize with ionomycin to stimulate a greater adhesion response than with each alone, and the [Ca2+]i-activation curve for ionomycin in the presence of PMA was shifted towards that for FMLP. Thus, synergy between [Ca2+]i and protein kinase C (each of which is sufficient alone) probably explains the stimulatory effects of FMLP on adhesion of neutrophils.
在相同的细胞制剂中测量了人中性粒细胞对塑料的刺激粘附以及胞质游离钙离子浓度[（Ca2+]i）的变化。构建了[Ca2+]i激活曲线，以比较[Ca2+]i与离子霉素和甲酰甲硫氨酰-亮氨酰-苯丙氨酸（FMLP）刺激下粘附之间的关系。结果表明，FMLP刺激的粘附比离子霉素的作用所需的[Ca2+]i增加量更少，这一结果表明，对FMLP的反应可能涉及额外的刺激成分。蛋白激酶C激活是一种可能，并且发现用佛波酯（PMA）激活蛋白激酶C可刺激粘附，而[Ca2+]i无变化。发现低浓度的PMA与离子霉素协同作用，比单独使用每种物质时刺激更大的粘附反应，并且在PMA存在下离子霉素的[Ca2+]i激活曲线向FMLP的曲线偏移。因此，[Ca2+]i与蛋白激酶C之间的协同作用（每种单独作用时都足够）可能解释了FMLP对中性粒细胞粘附的刺激作用。
