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The Effect of Leukotrienes on Heart Rate

Leukotrienes are potent hormone-like compounds that can affect virtually all organs, including the heart.

  1. Description

    • Along with prostaglandins and thromboxanes, leukotrienes belong to a class of compounds called eicosanoids. Some examples of leukotrienes are 5-HPTE, LTA4, LTB4, LTC4, LTD4 and LTE4.

    Synthesis

    • Synthesized in nearly every tissue of the body, leukotrienes are the product of the conversion of arachidonic acid by a family of enzymes called lipooxygenases.

    Function

    • As mediators of the allergic response and inflammation, leukotrienes cause the following: constriction of small blood vessels and bronchi (airway); smooth muscle contraction, increased blood vessel permeability, attraction of immune cells to a site of injury and enzyme release from immune cells.

    Cardiovacular Effects

    • In their text "Basic and Clinical Endocrinology" Drs. Greenspan and Gardner note that the major effects of leukotrienes on the heart include coronary (heart vessels) constriction, reduced contractility and reduced cardiac output. Leukotrienes, however, do not appear to have a direct significant effect on the heart rate.

    Leukotrienes in Disease Processes

    • Research studies, including one published in the American Journal of Respiratory Critical Care Medicine (volume 161), report a link between excess leukotriene production and such ailments as asthma, myocardial infarction (hear attack), stroke and anaphylaxis (severe allergic reaction).

    Considerations

    • While their direct effect on heart rate has little scientific support, leukotrienes may contribute indirectly to heart rate disturbances by stimulating certain disease processes. For instance, respiratory distress in asthma and anaphylaxis often manifests as increased heart rate, according to Medscape.

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