Contraction of guinea pig gall bladder strips by leukotrienes and other agonists

In the presence of indomethacin, Leukotriene C4 (LTC4), LTD4 and LTE4 were shown to be contractile agents in vitro on guinea pig gall bladder strips. The respective pD2 values for LTC4, LTD4 and LTE4 were 9.1, 9.1 and 7.7. The contractile effects of LTD4 were not mediated through the generation of cyclooxygenase products and were antagonized by the SRS-A antagonist FPL-55712. The effects of PGE1, PGF2 alpha, the endoperoxide analogue U44069 and histamine on gall bladder strips were also examined. All these agents caused dose-related contractions but were considerably less potent than the leukotrienes. Leukotrienes are therefore potent contractile agents on the guinea pig gall bladder and may contribute to gall bladder contractions or spasms in vivo.