Slow-reacting substance of anaphylaxis

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LTC4 Leukotriene C4.svg
LTC4
LTD4 Leukotriene D4.svg
LTD4
LTE4 Leukotriene E4.svg
LTE4

The slow-reacting substance of anaphylaxis or SRS-A is a mixture of the leukotrienes LTC4, LTD4 and LTE4. Mast cells secrete it during the anaphylactic reaction, inducing inflammation. [1] It can be found in basophils.

It induces prolonged, slow contraction of smooth muscle and has a major bronchoconstrictor role in asthma. [2] Compared to histamine, it is approximately 1000 times more potent and has a slower onset but longer duration of action.[ citation needed ]

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References

  1. "Dorland's Medical Dictionary". Archived from the original on January 9, 2007. Retrieved December 15, 2006.
  2. Howard R. Morris; Graham W. Taylor; Priscilla J. Piper; John R. Tippins (1980). "Structure of slow-reacting substance of anaphylaxis from guinea-pig lung". Nature. 285 (5760): 104–106. Bibcode:1980Natur.285..104M. doi:10.1038/285104a0. PMID   7374755 . Retrieved December 15, 2006.