The role of lipoxygenase and cyclooxygenase metabolites in acute hypoxic pulmonary vasoconstriction in piglets

Abstract

The role of lipoxygenase and cyclooxygeriase metabolites in acute hypoxic pulmonary vasoconstriction (HPV) was studied in piglets, it has been found that acute alveolar hypoxia induced remarkable pulmonary vasoconstrion, associated with an increase in cardiac output. The hypoxic pulmonary vasoconstriction response was insignificantly attenuated after infusion of DEC. indomethacin potentiated mar kedly the increase in pulmonary artery pressure and pulmonary vascular resistance and thus augmented HPV. It is inferred that hypoxic pulmonary vsaoconstriction in piglet may be mediated by other important mediators in addition to leukotrienes, but modulated by prostaglandins to prevent an excessive rise in pulmonary artery pressure.

References

[1] AhmedT, OliverW. Does slow-rea cting substance of anaphylaxis mediate hypo xic pulmonary v asoconstriction?. Am Rev Respir Dis, 1983, 127: 566-71

[2] MorganrothLM, et al. . Leukotriene synthesis and receptor blockers block hypoxic pulmonary vasoconstriction. J Appl Physiol, 1984, 56: 1340-6

[3] MorganrothLM, et al. . Diethylcarbamazine inhibits acute and chronic hypoxic pulmonary hypertension in awake rats. Am Rev Respir Dis, 1585, 131: 488-92

[4] VoelkelNF, et al. . Actions of lipoxygenase metabolites in isolated rat lungs. J Appl Physiol, 1984, 57: 8607-8607

[5] NaeijeR, et al. . Effects of diethylcarbamazine and cromolyn sodium on hypoxic pulmonary vasoconstriction in dogs. Bull Eur Physiopathol Respir, 1986, 22: 75-80

[6] GarretiRC, et al. . Lipoxygenase and cyclooxygenase blockade by BW 755C enhances pulmonary hypoxic vasoconstriction. J Appl Physiol, 1987, 62: 129-33

[7] LefflerCW, et al. . Cardiovascular effects of leukotrienes in neonatal piglets: role in hypoxic pulmonary vasoconstriction?. Circ Res, 1984, 55: 780-7

[8] MeyrickB, et al. . Pulmonary hypertension and increased vasoreactivity caused by repeated indomethacin in sheep. J Appl Physiol, 1985, 59: 443-52

[9] WalkerBR, et al. . Pulmonary response pressure after prostaglandin synthesis inhibition in conscious dogs. J Appl Physiol, 1982, 52: 705-9

[10] OminiC, et al. . Leukotriene C₄ induces generation of PG I₂ and TXA₂ in guinea pig in vivo. Pharmacol Res Commun, 1981, 13: 633-40

[11] TuckerA, et al. . Lung vascular smooth muscle as a determinant of pulmonary hypertension at high altitude. Am J Physiol, 1975, 228: 762-7