Leukotriene E4 (LTE4) is produced by the action of a dipeptidase on LTD4 leaving only the cysteinyl group still attached to the fatty acid backbone.1 It is one of the constituents of slow-reacting substance of anaphylaxis (SRS-A).2 LTE4 is considerably less active (8 to 12-fold) than LTC4 in the biological activities characteristic of cysteinyl LTs.1,3 Unlike LTC4 and LTD4, LTE4 accumulates in both plasma and urine. Therefore, urinary excretion of LTE4 is most often used as an indicator of asthma.4,5,6 LTE4 methyl ester is a more lipid soluble form of LTE4. The biological activity of LTE4 methyl ester has not been reported.
1
Bernström, K., and Hammarström, S. Metabolism of leukotriene D by porcine kidney. J Biol Chem2569579-9582(1981).
2
Samuelsson, B. Leukotrienes: Mediators of immediate hypersensitivity reactions and inflammation. Science220568-575(1983).
3
Lefer, A.M. Leukotrienes as mediators of ischemia and shock. Biochem Pharmacol35123-127(1986).
4
Kumlin, M., Stensvad, F., Larsson, L., et al. Validation and application of a new simple strategy for measurements of urinary leukotriene E4 in humans. Clin Exp Allergy25467-479(1995).
5
Drazen, J.M., O'Brien, J., Sparrow, D., et al. Recovery of leukotriene E4 from the urine of patients with airway obstruction. Am Rev Respir Dis146104-108(1992).
6
Kumlin, M., Dahlén, B., Björck, T., et al. Urinary excretion of leukotriene E4 and 11-dehydro-thromboxane B2 in response to bronchial provocations with allergen, aspirin, leukotriene D4, and histamine in asthmatics. Am Rev Respir Dis14696-103(1992).
Bernström, K., and Hammarström, S. Metabolism of leukotriene D by porcine kidney. J Biol Chem2569579-9582(1981).
Kumlin, M., Stensvad, F., Larsson, L., et al. Validation and application of a new simple strategy for measurements of urinary leukotriene E4 in humans. Clin Exp Allergy25467-479(1995).
Lefer, A.M. Leukotrienes as mediators of ischemia and shock. Biochem Pharmacol35123-127(1986).
Samuelsson, B. Leukotrienes: Mediators of immediate hypersensitivity reactions and inflammation. Science220568-575(1983).
Drazen, J.M., O'Brien, J., Sparrow, D., et al. Recovery of leukotriene E4 from the urine of patients with airway obstruction. Am Rev Respir Dis146104-108(1992).
Kumlin, M., Dahlén, B., Björck, T., et al. Urinary excretion of leukotriene E4 and 11-dehydro-thromboxane B2 in response to bronchial provocations with allergen, aspirin, leukotriene D4, and histamine in asthmatics. Am Rev Respir Dis14696-103(1992).