[Possible significance of the lipoxygenase pathway of arachidonic acid metabolism for the pathogenesis of constrictive reactions of lung blood vessels].
Recent studies suggest a key role of lipoxygenase (LOX) pathway of arachidonic acid (AA) metabolism in the regulation of pulmonary artery tone. We investigated the influence of specific inhibition of leucotriene biosynthesis on constrictory reactions of isolated rabbit pulmonary arteries in the organ bath. The substance FLM 5,011 selectively inhibiting the LOX pathway leads at a bath concentration of 5 X 10(-5) M to an inhibition in the order of 75% of AA- and phospholipase (PLP) A2-induced contraction (cumulative measurement, 37 degrees C, pH 7.4, isotonic contraction). The inhibitory effect on calciumionophore A 53,712-induced contraction was only 31.4%. We compared these findings with actions of nordihydroguiaretic acid and PAMBA. Our findings suggest that in rabbit lung arteries receptors for AA-products must exist and that the activation of AA depends on calcium. The present investigations underline the relevance of LOX products to genesis of pulmonary hypertension in man.
D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism*; D006801:Humans; D006976:Hypertension, Pulmonary / Q000503:physiopathology*; D008084:Lipoxygenase / Q000502:physiology*; D008173:Lung Diseases, Obstructive / Q000503:physiopathology*; D009131:Muscle, Smooth, Vascular / Q000503:physiopathology; D011651:Pulmonary Artery / Q000503:physiopathology; D014661:Vasoconstriction
D001095:Arachidonic Acids; D016718:Arachidonic Acid; D008084:Lipoxygenase
Mögliche Bedeutung des Lipoxygenaseweges des Arachidonsäuremetabolismus für die Pathogenese konstriktorischer Reaktionen an Lungengefässen.