title: Unglycosylated rat alpha 1-proteinase inhibitor has a six-fold shorter plasma half-life than the mature glycoprotein.
abstract: The plasma half-lives of glycosylated and unglycosylated alpha 1-proteinase inhibitor-radioactively labeled with [35S]methionine in rat hepatocyte primary cultures - were determined in the rat. Unglycosylated alpha 1-proteinase inhibitor was synthesized by hepatocytes in the presence of tunicamycin. Media from hepatocytes containing 35S-labeled glycosylated or unglycosylated alpha 1-proteinase inhibitor were injected into the tail veins of rats. At different times after injection alpha 1-proteinase inhibitor was isolated from plasma by affinity chromatography with anti-alpha 1-proteinase inhibitor Sepharose. Radioactivity measurements revealed a plasma half-life of 170 min for glycosylated alpha 1-proteinase inhibitor and of 30 min for the unglycosylated form of the inhibitor.
mesh_terms: D000818:Animals; D001798:Blood Proteins; D002241:Carbohydrates / Q000097:blood*; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D006207:Half-Life; D008099:Liver / Q000378:metabolism; D008297:Male; D011480:Protease Inhibitors / Q000097:blood*; D051381:Rats; D011919:Rats, Inbred Strains; D014415:Tunicamycin / Q000494:pharmacology; D000515:alpha 1-Antitrypsin
chemical_list: D001798:Blood Proteins; D002241:Carbohydrates; D011480:Protease Inhibitors; D000515:alpha 1-Antitrypsin; D014415:Tunicamycin