Thromboxane mediates the increase in alveolar surfactant pool induced by free fatty acid infusion in the rabbit.
Intravenous infusion of free fatty acid (FFA) produces pulmonary edema and an increase in the alveolar surfactant content of the rabbit. In order to identify a likely mediator of this lung response to FFA, we used inhibitors of cyclo-oxygenase (indomethacin, 15 mg X kg-1 i.v., or meclofenamate, 5 mg X kg-1 i.v.) and thromboxane synthetase inhibitors (imidazole, 50 mg X kg-1 i.v. or dazoxiben, 2 mg X kg-1 i.v.) which were administered before FFA, 20 mg X kg-1 X min-1 i.v., in four different experimental series (n = 54). Lung surfactant was measured in bronchial-alveolar lavage fluid by determining disaturated phosphatidylcholine (DSPC). Both kinds of inhibitors blocked the increase in FFA-induced DSPC. They increased the survival rate but they only slightly changed the post-FFA morphofunctional pulmonary alterations. We conclude that the increase in alveolar surfactant induced by FFA is likely mediated by thromboxane. This mediator would seem to play a minor role in the FFA-induced pulmonary edema observed.
D000818:Animals; D002245:Carbon Dioxide / Q000097:blood; D016861:Cyclooxygenase Inhibitors; D005230:Fatty Acids, Nonesterified / Q000494:pharmacology*; D007093:Imidazoles / Q000494:pharmacology; D007213:Indomethacin / Q000494:pharmacology; D008170:Lung Compliance / Q000187:drug effects; D008297:Male; D008469:Meclofenamic Acid / Q000494:pharmacology; D010100:Oxygen / Q000097:blood; D011650:Pulmonary Alveoli / Q000187:drug effects* / Q000503:physiopathology; D011654:Pulmonary Edema / Q000139:chemically induced* / Q000503:physiopathology; D011663:Pulmonary Surfactants / Q000096:biosynthesis*; D011817:Rabbits; D013930:Thromboxane-A Synthase / Q000037:antagonists & inhibitors; D013931:Thromboxanes / Q000502:physiology*
D016861:Cyclooxygenase Inhibitors; D005230:Fatty Acids, Nonesterified; D007093:Imidazoles; D011663:Pulmonary Surfactants; D013931:Thromboxanes; C029166:dazoxiben; D002245:Carbon Dioxide; D008469:Meclofenamic Acid; C029899:imidazole; D013930:Thromboxane-A Synthase; D010100:Oxygen; D007213:Indomethacin