Possible induction of fatty acid cyclo-oxygenase in lipopolysaccharide-stimulated rat Kupffer cells.
In response to stimulation with lipopolysaccharide, isolated rat Kupffer cells released increased amounts of prostaglandin E2, prostaglandin D2, 6-keto-prostaglandin F1 alpha, and thromboxane B2. There was a lag of 2-6 hours before a significant release of these metabolites into the medium was detected. Nonstimulated Kupffer cells converted exogenous arachidonic acid to prostaglandins and thromboxane B2, and a major product was prostaglandin D2. Twenty-four hours after stimulation with lipopolysaccharide, Kupffer cells produced approximately 7 times more prostaglandin E2 and 2 times more prostaglandin D2, 6-keto-prostaglandin F1 alpha; and thromboxane B2 than nonstimulated cells. Western immunoblotting of microsomal proteins prepared from the stimulated rat Kupffer cells showed a 70-kilodalton component that was immunoreactive with a polyclonal anticyclo-oxygenase antibody. The intensity of the band increased with the time of the lipopolysaccharide stimulation. These results suggest that the accelerated arachidonate metabolism in lipopolysaccharide-stimulated rat Kupffer cells might be attributed to an induction of the cyclo-oxygenase enzyme.
Kawada
N
N
Third Department of Internal Medicine, Osaka City University Medical School, Japan.
Mizoguchi
Y
Y
Kobayashi
K
K
Monna
T
T
Morisawa
S
S
Ueda
N
N
Omoto
Y
Y
Takahashi
Y
Y
Yamamoto
S
S
D015121:6-Ketoprostaglandin F1 alpha / Q000378:metabolism*; D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism*; D015153:Blotting, Western; D002851:Chromatography, High Pressure Liquid; D015232:Dinoprostone / Q000378:metabolism*; D004790:Enzyme Induction / Q000187:drug effects; D007728:Kupffer Cells / Q000201:enzymology*; D008070:Lipopolysaccharides; D008297:Male; D015230:Prostaglandin D2 / Q000378:metabolism*; D011451:Prostaglandin-Endoperoxide Synthases / Q000032:analysis / Q000096:biosynthesis*; D051381:Rats; D013929:Thromboxane B2 / Q000378:metabolism*
D008070:Lipopolysaccharides; D016718:Arachidonic Acid; D013929:Thromboxane B2; D015121:6-Ketoprostaglandin F1 alpha; D011451:Prostaglandin-Endoperoxide Synthases; D015232:Dinoprostone; D015230:Prostaglandin D2