Action and metabolism of circulating leukotriene C.

The microvascular permeability effects of intravenously administered leukotriene C4 were assessed by fluorometric determinations of extravasated Evans blue dye in various tissues of guinea pigs. The effects were widespread, with intensity differences between different vascular beds, which in part reflected the tissue distribution of tritium-labeled leukotriene C3 in mice. Local tissue specificity favored permeability effects in the urinary tract, pulmonary airways, esophagus, and distal colon. The permeability effects may contribute to the hypotensive actions of leukotriene C4 and enhance airway obstruction by edema formation in addition to smooth muscle contraction.