Influence of hypoxia on 5-lipoxygenase pathway in rat alveolar macrophages.
The effect of hypoxia was studied on the ionophore A23187-induced leukotriene production by rat alveolar macrophages. The production of LTB4 and LTC4 decreased with reducing oxygenation without change of cell viability. The synthesis of 5-HETE increased during hypoxia and the total production of LTB4, LTC4 and 5-HETE, the major metabolites of the 5-lipoxygenase pathway in rat alveolar macrophages, was equal during normoxia and hypoxia. Arachidonate release and LTA4-converting into LTB4 and LTC4 was unaffected by hypoxia. LTB4- and LTC4-degradating activities were not affected by hypoxia. These results suggest that LTA4 synthase reaction of leukotrienes biosynthesis might be suppressed by hypoxia.
Ohwada
A
A
Department of Respiratory Medicine, School of Medicine, Juntendo University, Tokyo, Japan.
Kira
S
S
Yamashita
T
T
D000818:Animals; D001094:Arachidonate 5-Lipoxygenase / Q000378:metabolism*; D001091:Arachidonate Lipoxygenases / Q000378:metabolism*; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism; D002417:Cattle; D006893:Hydroxyeicosatetraenoic Acids / Q000378:metabolism; D000860:Hypoxia / Q000378:metabolism*; D017572:Leukotriene A4; D007975:Leukotriene B4 / Q000378:metabolism; D015289:Leukotrienes / Q000096:biosynthesis / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism*; D008297:Male; D011650:Pulmonary Alveoli / Q000166:cytology; D051381:Rats; D011919:Rats, Inbred Strains; D013189:SRS-A / Q000378:metabolism; D014316:Tritium
D001095:Arachidonic Acids; D006893:Hydroxyeicosatetraenoic Acids; D017572:Leukotriene A4; D015289:Leukotrienes; D013189:SRS-A; D014316:Tritium; D007975:Leukotriene B4; D016718:Arachidonic Acid; C022022:5-hydroxy-6,8,11,14-eicosatetraenoic acid; D001091:Arachidonate Lipoxygenases; D001094:Arachidonate 5-Lipoxygenase