Krause H, Dieter P, Schulze-Specking A, Ballhorn A, Ferber E, Decker K
Biochemisches Institut, Albert-Ludwigs-Universität, Freiburg, Germany.
Biochem Biophys Res Commun. 1991 Mar 15;175(2):532-6. doi: 10.1016/0006-291x(91)91597-6.
In cell-free extracts of rat liver macrophages (Kupffer cells) phospholipase A2 was found to be strongly activated at free Ca2+ concentrations from 100 nM to 1 microM in the presence of 4 mM free Mg2+. This is within the range of intracellular free Ca2+ reported for basal and various stimulated conditions, respectively. Ca2+ alone increased phospholipase A2 activity at high Ca2+ concentrations (1 mM) whereas Mg2+ alone had only little stimulatory effect. Calmodulin does not seem to participate in the regulation of phospholipase A2 although it relieved the inhibition of phospholipase A2 activity by calmodulin antagonists.
在大鼠肝脏巨噬细胞（库普弗细胞）的无细胞提取物中，发现磷脂酶A2在4 mM游离镁存在的情况下，当游离钙离子浓度在100 nM至1 microM之间时会被强烈激活。这分别处于报道的基础状态和各种刺激条件下细胞内游离钙离子的浓度范围内。单独的钙离子在高钙离子浓度（1 mM）时会增加磷脂酶A2的活性，而单独的镁离子只有很小的刺激作用。钙调蛋白似乎不参与磷脂酶A2的调节，尽管它能解除钙调蛋白拮抗剂对磷脂酶A2活性的抑制。
