title: Atrial natriuretic polypeptides (ANP): rat atria store high molecular weight precursor but secrete processed peptides of 25-35 amino acids.
abstract: A radioimmunoassay was developed for rat atrial natriuretic polypeptides. Using the radioimmunoassay and gel filtration in reducing and dissociating conditions, extracts of rat atria were found to contain mainly a 15000-dalton immunoreactive material, probably corresponding to pronatriodilatin. However, when isolated beating atria were incubated in plasma-free conditions, the secreted immunoreactive material consisted almost exclusively of 2500-3500-dalton peptide(s). These results show that rat atrial cells secrete a low molecular weight natriuretic peptide which is highly active, but store the less active large molecular weight form(s).
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D009320:Atrial Natriuretic Factor; D002850:Chromatography, Gel; D006325:Heart Atria / Q000378:metabolism; D008297:Male; D008970:Molecular Weight; D009124:Muscle Proteins / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D045283:Natriuretic Agents; D011498:Protein Precursors / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D000596:Amino Acids; D009124:Muscle Proteins; D045283:Natriuretic Agents; D011498:Protein Precursors; D011506:Proteins; D009320:Atrial Natriuretic Factor