title: Increase of anti-ulcerogenic activity by reduction and alkylation of disulfide bonds of a globulin fraction from bovine serum.
abstract: Bovine serum was subjected to ammonium sulfate fractionation, and subsequently chromatographed on DEAE-cellulose column to obtain a globulin protein having a weak anti-ulcerogenic activity, Fr.II-A. Agar immunoelectrophoresis and immunodiffusion using rabbit antiserum against bovine IgG revealed that Fr.II-A from bovine serum shared antigenic determinant with bovine IgG. Furthermore, Fr.II-A showed a single band on polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. By reducing and alkylating the disulfide bonds by 2-mercaptoethanol and iodoacetic acid, Fr.II-A was separated into two subfragments in the same manner as in the case of immunoglobulin to produce Fr.L (molecular weight; 24000) and Fr.H (molecular weight; 50000). Fr.L showed anti-ulcerogenic activity up to about ten times greater than that of original Fr.II-A, but in the case of Fr.H, the activity increased approximately several times. Fr.L showed significant activity in preventing ulcer formation and gastric juice secretion in pylorus-ligated rats, and was also effective in reducing index of the phenylbutazone-induced ulcer.
mesh_terms: D000478:Alkylation; D000818:Animals; D000897:Anti-Ulcer Agents; D002850:Chromatography, Gel; D004220:Disulfides; D004591:Electrophoresis, Polyacrylamide Gel; D005916:Globulins / Q000494:pharmacology*; D007120:Immunochemistry; D005779:Immunodiffusion; D008297:Male; D010084:Oxidation-Reduction; D051381:Rats; D011919:Rats, Inbred Strains; D013276:Stomach Ulcer / Q000139:chemically induced / Q000188:drug therapy
chemical_list: D000897:Anti-Ulcer Agents; D004220:Disulfides; D005916:Globulins