Inhibition of 5-lipoxygenase-activating protein (FLAP) reduces pulmonary vascular reactivity and pulmonary hypertension in hypoxic rats - PubMed (original) (raw)

Inhibition of 5-lipoxygenase-activating protein (FLAP) reduces pulmonary vascular reactivity and pulmonary hypertension in hypoxic rats

N F Voelkel et al. J Clin Invest. 1996.

Abstract

Chronically elevated shear stress and inflammation are important in hypertensive lung vessel remodeling. We postulate that 5-lipoxygenase (5-LO) is a molecular determinant of these processes. Immunohistology localized the 5-LO to macrophages of normal and chronically hypoxic rat lungs and also to vascular endothelial cells in chronically hypoxic lungs only. In situ hybridization of normal and chronically hypoxic lungs demonstrated that 5-LO mRNA is expressed in macrophages. Rats hypoxic for 4 wk-developed pulmonary hypertension increased translocation of the lung 5-LO from the cytosol to the membrane fraction and increased levels of lung tissue 5-lipoxygenase-activating protein (FLAP). A FLAP ligand, 3-[l-(4-chlorobenzyl)-3-t-butyl-thio-t-isopropylindol-2-yl]-2,2- dimethylpropanoic acid (MK-886), inhibited the acute angiotensin II and hypoxia-induced pulmonary vasoconstriction in vitro and the development of chronic hypoxic pulmonary hypertension in rats in vivo. Mice bred with the deletion of the 5-LO enzyme (5-LO knockout) developed less right heart hypertrophy than age-matched 5-LO competent mice. Our results support the hypothesis that the 5-LO is involved in lung vascular tone regulation and in the development of chronic pulmonary hypertension in hypoxic rodent models.

PubMed Disclaimer

Similar articles

Cited by

References

    1. Circ Res. 1976 Feb;38(2):99-104 - PubMed
    1. FASEB J. 1995 Feb;9(2):183-9 - PubMed
    1. Am J Physiol. 1985 Jun;248(6 Pt 2):H859-66 - PubMed
    1. J Biol Chem. 1986 Dec 15;261(35):16466-72 - PubMed
    1. Prostaglandins. 1986 Dec;32(6):857-73 - PubMed

Publication types

MeSH terms

Substances

LinkOut - more resources