George M, Chepenik K P
Biochim Biophys Acta. 1985 Aug 22;836(1):45-55. doi: 10.1016/0005-2760(85)90218-8.
Incubation of palate mesenchyme cells in vitro in the presence of [3H]arachidonate and [14C]palmitate resulted in incorporation of radiolabel into all major families of phospholipids. Almost all (more than 90%) of the 3H and about one-half of the 14C in the phospholipids were in the sn-2 position. The [14C] fatty acid in the sn-2 position was saturate. When [14C]stearate was added to the culture medium with [3H]arachidonate, 30-40% of the total 14C in phospholipids was in the sn-2 position. 80% of the 14C in the sn-2 position was found in unsaturated fatty acids. Hydrolysis of phospholipids could be demonstrated at acid, neutral and alkaline pH. Calcium stimulated phospholipase activity at neutral and alkaline pH, but inhibited hydrolytic activity at acid pH. Radiolabeled lysophospholipid indicative of phospholipase A2 activities accumulated at acid pH, whereas little, if any, radiolabeled lysophospholipids accumulated at neutral and alkaline pH. Quantitative analysis revealed the production of some lysophosphatidylethanolamine at alkaline pH.
在含有[3H]花生四烯酸和[14C]棕榈酸的条件下，体外培养腭间充质细胞，结果导致放射性标记掺入所有主要磷脂家族。磷脂中几乎所有（超过90%）的3H和约一半的14C处于sn-2位。sn-2位的[14C]脂肪酸是饱和的。当将[14C]硬脂酸与[3H]花生四烯酸一起添加到培养基中时，磷脂中总14C的30-40%处于sn-2位。sn-2位中80%的14C存在于不饱和脂肪酸中。在酸性、中性和碱性pH条件下均可证明磷脂的水解。钙在中性和碱性pH条件下刺激磷脂酶活性，但在酸性pH条件下抑制水解活性。指示磷脂酶A2活性的放射性标记溶血磷脂在酸性pH条件下积累，而在中性和碱性pH条件下几乎没有（如果有的话）放射性标记溶血磷脂积累。定量分析显示在碱性pH条件下产生了一些溶血磷脂酰乙醇胺。
