Biosynthesis of heparin. Effects of n-butyrate on cultured mast cells.

摘要: Murine mastocytoma cells were incubated in vitro with inorganic [35S]sulfate, the absence or presence of 2.5 mM n-butyrate, and labeled heparin was isolated. The polysaccharide produced butyrate showed a lower charge density on anion exchange chromatography than did control material 3-fold increased proportion (54 versus 17% for control) components high affinity antithrombin. Structural analysis [3H] glucosamine that approximately 35% units N-acetylated, as compared to 10% material; nonacetylated residues N-sulfated. thus leads an inhibition N-deacetylation/N-sulfation process biosynthesis, along augmented formation molecules Preincubation required manifestation either effect; when preincubation period reduced from 24 10 h effects no longer observed. Assays microsomal N-acetylheparosan deacetylase activity failed show any significant enzyme at concentrations well above those found affect biosynthesis intact cells. Moreover, formed incubating fraction UDP-[3H]glucuronic acid, UDP-N-acetylglucosamine, 3'-phosphoadenylylsulfate 5 same N-acetyl/N-sulfate ratio corresponding polysaccharide, butyrate. These findings suggest effect depends integrity cell.