title: Atrial natriuretic factor (ANF) prohormone accumulates in the IgG fraction of anti-ANF hybridoma-bearing mice.
abstract: We demonstrate immunoreactive mouse atrial natriuretic factor (ANF) in the IgG fraction prepared from ascites or serum of mice bearing an anti-rat ANFArg101-Tyr126 hybridoma. The HPLC profile of the ANF demonstrates that the IgG fraction contains both mature ANFSer99-Tyr126 and the prohormone ANFAsn1-Tyr126. The presence of circulating prohormone in the hybridoma-bearing mice is not secondary to changes in fluid volume due to ascites formation. The anti-ANF antibody appears to protect the ANFAsnl-Tyr126 from both maturation and rapid receptor-mediated clearance. Our results suggest, therefore, that the ANFAsn1-Tyr126 can be secreted into a compartment that is accessible to antibody and that maturation of the ANF prohormone may be an extracellular event.
authors.affiliation: Lipoprotein and Atherosclerosis Group, University of Ottawa Heart Institute, Ontario, Canada.
authors.forename: R W
authors.initials: RW
authors.lastname: Milne
authors.forename: J
authors.initials: J
authors.lastname: Gutkowska
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D000937:Antigen-Antibody Reactions; D001201:Ascites; D009320:Atrial Natriuretic Factor / Q000276:immunology / Q000378:metabolism*; D002451:Cell Compartmentation; D006825:Hybridomas; D007074:Immunoglobulin G / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D011498:Protein Precursors / Q000378:metabolism*; D017461:Receptors, Atrial Natriuretic Factor / Q000378:metabolism; D011993:Recombinant Fusion Proteins
chemical_list: D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; D011498:Protein Precursors; D011993:Recombinant Fusion Proteins; D009320:Atrial Natriuretic Factor; D017461:Receptors, Atrial Natriuretic Factor