Predominant synthesis of 5-hydroxyeicosatetraenoic acid by a cloned mastocytoma P-815 line, 2-E-6 cells.
Since mouse mast tumor P-815 cells produce the slow reacting substance of anaphylaxis, their 5-lipoxygenase activity was examined by determining the conversion of arachidonic acid to 5-hydroxyeicosatetraenoic acid (HETE). Mast tumor cells from mouse ascites fluid synthesized 12-HETE as a major and 5-HETE as a minor metabolite. Once the cells were transferred to an in vitro culture system, the predominant synthesis of 12-HETE was abolished and synthesis of 5-HETE was greater than that of 12-HETE. 2-E-6 cells, obtained by cloning the tumor cells, synthesized a negligible amount of 12-HETE, but produced a large amount of 5-HETE. When the 2-E-6 cells were inoculated into mice and harvested again from the ascites fluid, their ratio of 5-HETE to 12-HETE synthesis was similar to that of normal mouse peritoneal cells; that is, 12-HETE synthesis was much greater than 5-HETE synthesis. It is concluded that the predominant synthesis of 12-HETE in mast tumor cells was derived from natural peritoneal cells, which have very high 12-lipoxygenase activity. The cloned mastocytoma, 2-E-6 cells, should be useful in investigating regulation of 5-lipoxygenase activity.
D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; D000818:Animals; D001095:Arachidonic Acids / Q000096:biosynthesis; D002460:Cell Line; D002999:Clone Cells; D004537:Eicosanoic Acids / Q000096:biosynthesis*; D013058:Mass Spectrometry; D012515:Mast-Cell Sarcoma / Q000378:metabolism*; D051379:Mice
C025347:5-hydroxyarachidic acid; D001095:Arachidonic Acids; D004537:Eicosanoic Acids; D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid