INTERACTION BETWEEN LEUKOTRIENE-C4 AND HISTAMINE IN THE GUINEA-PIG

Abstract

Lipoxygenase metabolites have proposed as potential chemical mediators of the bronchial hyperractivity which characterizes asthma (2,6). In addition to the possibility that leukotrienes (LTs) sensitize airways smooth muscle to the contractile actions of other mediators such as histamine (1-3), a number of studies have provided evidence for LT-induced enhancement of bronchoconstriction by a vagal dependent mechanism (4-6). In the present study the effects of exposure of the airway to LTC on subsequent responsiveness to histamine have been investigated in both in vitro and in vivo experiments. LTC , in a concentration eliciting threshold contractile responses of the isolated trachea (1.7 nM),..