Effects of leukotriene E on pulmonary mechanics in the guinea pig.

The effects of intravenously infused 5(S)hydroxy-6(R)-S-cysteinyl-7,9,-trans,11,14,-cis eicosatetraenoic acid (leukotriene E) (LTE), one of the leukotriene constituents of slow-reacting substance of anaphylaxis (SRS-A), on pulmonary resistance (RL) and dynamic compliance (Cdyn), breathing frequency, and mean systemic arterial pressure were determined in both anesthetized and unanesthetized guinea pigs. The LTE caused a dose-dependent increase of RL and decrease in Cdyn over the range of doses from 100 to 10,000 ng/kg with significance effects at the highest doses. The onset of effect after a significant dose occurred within 30 s and was maximal 1 to 3 min after infusion. The LTE elicits a significantly greater effect on RL for a given change in Cdyn than occurs with LTC or LTD indicating that LTE is a less selective peripheral airway agonist than LTC or LTD. The LTD infusion resembled LTC or LTD in evoking a systemic arterial hypotension that was preceded by a brief initial period of hypertension in unanesthetized animals.