Investigation of leukotriene involvement in the vasopermeability response associated with guinea pig tracheal anaphylaxis: comparison with cutaneous anaphylaxis.

A direct comparison of the role of leukotrienes in mediating the increase in microvascular permeability associated with guinea pig tracheal and cutaneous anaphylaxis was obtained by simultaneous administration of inflammatory stimuli to both trachea and ear. The SRS-A antagonist, FPL 55712, reduced the increase in tracheal extravascular albumin content evoked by LTC4, LTD4, and LTE4 but failed to significantly reduce the tracheal microvascular permeability response associated with local anaphylaxis. Moreover, the inhibitory effect of the histamine H1-receptor antagonist, mepyramine, was not augmented by the additional presence of FPL 55712. In contrast to tracheal anaphylaxis, a distinct leukotriene component was indicated in cutaneous anaphylaxis since the mepyramine-FPL 55712 combination produced a greater inhibition than mepyramine alone. These results suggest that the degree of leukotriene involvement in anaphylaxis may vary between tissues.