Effects of tartrazine of different contractile stimuli in guinea pig tracheal muscle.

Tracheal smooth muscle obtained from ovalbumin-sensitized guinea pigs contracted with micromolar concentrations of tartrazine and indomethacin. The contractions were slightly reduced by clemastine, but were completely blocked by the SRS-A antagonist FPL 55712. Arylsulfatase B, which is an enzyme that inactivates SRS-A, also abolished the contractions induced by tartrazine. Contractions induced by carbacholine, histamine, egg albumin and arachidonic acid were slightly reduced by indomethacin and tartrazine. Tartrazine like indomethacin inhibited the generation of thromboxanes from human platelets. We suggest that SRS-A plays an important role in the immediate hypersensitivity reactions of tartrazine and indomethacin in guinea pig trachea.