STRUCTURE-ACTIVITY OF THREE PHOSPHOLIPID ANALOGUES TOWARDS INHIBITION OF PHOSPHOLIPASE A2 IN MACROPHAGES

At concentrations 1–20gmMin culture medium of rat peritoneal macrophages which were stimulated with ionophore A23187, the phospholipid analogues 1-decyl-2-octyl-glycero- phosphocholine and 1-dodecyl-2-octanamido-2-deoxy glycerophosphocholine were found more potent inhibitors than 1-octyl-2-octylthio-2-deoxy glycerophosphocholine to lower the phospholipase A2activities. The inhibitory effect was measured by [3H] eicosatetraenoic acid ([3H]20:4) release in macrophages and extracellular fluids and synthesis of [3H] eicosanoids after incubation of macrophages with traces of the molecular species of lecithin 1-octadecanoyl-2-[3H] eicosatetraenoyl glycerophosphocholine. The three phospholipid analogues developed higher inhibitory effects than mepacrine, dexamethasone or bromophenacyl bromide, at corresponding concentrations in medium.