Flesch I, Schonhardt T, Ferber E
Max-Planck-Institut für Immunbiologie, Freiburg.
Klin Wochenschr. 1989 Feb 1;67(3):119-22. doi: 10.1007/BF01711335.
In contrast to many other cells, macrophages contain a phospholipase A2, which preferentially liberates arachidonic acid from the main phospholipids. In unstimulated macrophages this acylchain-specific phospholipase A2 is localized in the lipid-free cytosol and thus without function. After activation of protein kinase C with diacylglycerols, the cytosolic phospholipase A2 is translocated to cellular membranes. The same activator of protein kinase C causes an inhibition of the acyl-CoA: lysophosphatide acyltransferase. This enzyme regulates the availability of free arachidonic acid for eicosanoid synthesis by reacylation into phospholipids. Thus protein kinase C seems to regulate the level of free arachidonic acid by opposite effects on the two major enzymes, which are responsible for the control of free arachidonic acid.
与许多其他细胞不同，巨噬细胞含有一种磷脂酶A2，它优先从主要磷脂中释放花生四烯酸。在未受刺激的巨噬细胞中，这种酰基链特异性磷脂酶A2定位于无脂质的细胞质溶胶中，因此没有功能。在用二酰基甘油激活蛋白激酶C后，细胞质磷脂酶A2转移到细胞膜。蛋白激酶C的同一激活剂会抑制酰基辅酶A：溶血磷脂酰基转移酶。该酶通过再酰化进入磷脂来调节游离花生四烯酸用于类花生酸合成的可用性。因此，蛋白激酶C似乎通过对负责控制游离花生四烯酸的两种主要酶产生相反作用来调节游离花生四烯酸的水平。
