Airway constrictor effects of leukotriene D4 in dogs with hyperreactive airways.

Leukotriene D4 (5 micrograms/ml) aerosol constricts airways of dogs with nonspecific airway hyperreactivity but not of mongrel dogs which lack nonspecific airway hyperreactivity. RL increased 200 +/- 25% and Cdyn decreased to 77 +/- 5% of the prechallenge value. LTD4 (10 micrograms/ml) produced no further increase. Atropine (0.2 mg/kg) prevented the increase in RL and decrease in Cdyn, suggesting that part of the effect of LTD4 on airways is neurally mediated.