Antigenic stimulated release of arachidonic acid, lipoxygenase activity and histamine release in a cloned murine mast cell MC9.
A cloned murine mast cell MC9 expresses phospholipase and lipoxygenase activity when stimulated with IgE and hapten. Addition of DNP-BSA to sensitized MC9 cells causes release of 58% of the cell histamine and 127 pmoles LTC4/10(6) cells. Prelabelling studies with [1-14C]-arachidonic acid showed that LTC4 production was proceeded by the release of arachidonic acid from membrane phospholipids. Approximately 8.7% of the cell arachidonic acid was released and half of this was converted to LTC4. The remaining radioactivity was converted to diHETES including LTB4 (15%), 5-HETE (10%), free arachidonic acid (10%), reesterified 5-HETE and arachidonic acid (8%) and prostaglandins (7%). This stimulation was dependent on hapten (DNP-BSA) and extracellular Ca++. Under identical conditions the calcium ionophore A23187 stimulated the release of 10.3% of the total cell arachidonic acid, and 51% of this was metabolized to LTC4. In addition the ionophore stimulated the release of 61% of the total cellular histamine.
Musch
M W
MW
Siegel
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MI
D000818:Animals; D001091:Arachidonate Lipoxygenases; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism*; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology; D002999:Clone Cells / Q000276:immunology; D004140:Dinitrophenols; D004789:Enzyme Activation; D006241:Haptens; D006636:Histamine Release; D007073:Immunoglobulin E; D008084:Lipoxygenase / Q000378:metabolism*; D008407:Mast Cells / Q000276:immunology*; D051379:Mice; D013189:SRS-A / Q000378:metabolism; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D013997:Time Factors
D001095:Arachidonic Acids; D004140:Dinitrophenols; D006241:Haptens; D013189:SRS-A; C034638:dinitrophenyl-bovine serum albumin; D012710:Serum Albumin, Bovine; D016718:Arachidonic Acid; D007073:Immunoglobulin E; D000001:Calcimycin; D001091:Arachidonate Lipoxygenases; D008084:Lipoxygenase; D002118:Calcium