Leukotriene B4-d4 (LTB4-d4) contains four deuterium atoms at the 6, 7, 14, and 15 positions. It is intended for use as an internal standard for the quantification of LTB4 by GC- or LC-mass spectrometry. LTB4 is a dihydroxy fatty acid derived from arachidonic acid through the 5-lipoxygenase pathway. It promotes a number of leukocyte functions including aggregation, stimulation of ion fluxes, enhancement of lysosomal enzyme release, superoxide anion production, chemotaxis, and chemokinesis. In subnanomolar ranges (3.9 x 10?10 M), LTB4 causes chemotaxis and chemokinesis in human PMNL. At higher concentrations, (1.0 x 10?7 M), LTB4 leads to neutrophil aggregation and degranulation as well as superoxide anion production.
