The contribution of hepatocytes to prostaglandin synthesis in rat liver.
The contribution of hepatocytes to liver prostaglandin (PG) synthesis Is not clear. We compared prostaglandin synthesis in homogenates of whole liver, freshly isolated hepatocytes, and mixed non-parenchymal cells from the same rat livers, and optimized the assay. Whole liver homogenates made 27.2 +/- 7.1 mg PGE2/mg protein/5 min (+/- SEM, n = 4 livers). Hepatocyte homogenates made 39 +/- 9% as much PGE2/mg protein as did the matched whole livers. Non-parenchymal cell homogenates made slightly more PGE2 than whole liver, but much more PGD2. Subsequent studies showed that fresh hepatocyte suspensions contain significant contamination with non-parenchymal cells. Homogenates from ricin-purified hepatocyte monolayers made at least half as much PGE2 as did conventional monolayers. However, taking cellular purity into account, hepatocytes must contain much less than a third of liver cyclooxygenase activity.
D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism; D002469:Cell Separation; D002478:Cells, Cultured; D017364:Collagenases / Q000494:pharmacology; D015232:Dinoprostone / Q000096:biosynthesis*; D004731:Endotoxins / Q000494:pharmacology; D004926:Escherichia coli; D007700:Kinetics; D008099:Liver / Q000166:cytology* / Q000378:metabolism*; D008297:Male; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012276:Ricin
D004731:Endotoxins; D011506:Proteins; D016718:Arachidonic Acid; D012276:Ricin; D011451:Prostaglandin-Endoperoxide Synthases; D017364:Collagenases; D015232:Dinoprostone