title: Atrial natriuretic factor-like peptide and its prohormone within single cell organisms.
abstract: The present investigation was designed to determine if the atrial natriuretic peptide hormonal system is present within single cell organisms. Paramecium multimicronucleatum were examined with 3 sensitive and specific radioimmunoassays which recognize the N-terminus [amino acids 1-98; proANF(1-98)], the midportion of the N-terminus [amino acids 31-67; proANF(31-67)] and C-terminus (amino acids 99-126; ANF) of the 126 amino acid atrial natriuretic factor (ANF) prohormone. ProANF(1-98), proANF(31-67), and ANF-like peptides were all present within these unicellular organisms at concentrations of 460 +/- 19 pg/ml, 420 +/- 15 pg/ml, and 14.5 +/- 2 pg/ml, respectively. These concentrations are similar to their respective concentrations in the plasma of the rat (Rattus norvegicus). These results suggest that even single cell organisms contain the atrial natriuretic peptide-like hormonal system.
authors.affiliation: Department of Medicine, University of South Florida Health Sciences Center, Tampa 33612.
authors.forename: D L
authors.initials: DL
authors.lastname: Vesely
authors.forename: A T
authors.initials: AT
authors.lastname: Giordano
mesh_terms: D000328:Adult; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000032:analysis* / Q000276:immunology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010247:Paramecium / Q000737:chemistry*; D010446:Peptide Fragments / Q000276:immunology; D011498:Protein Precursors / Q000032:analysis* / Q000276:immunology; D011863:Radioimmunoassay / Q000379:methods*; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D010446:Peptide Fragments; D011498:Protein Precursors; C054548:atrial natriuretic factor prohormone (31-67); C055659:atrial natriuretic factor prohormone (1-98); D009320:Atrial Natriuretic Factor