title: Atrial natriuretic peptide synthesis in atrial tumors of transgenic mice.
abstract: Transgenic mice harboring a chimeric gene linking mouse protamine 1 5'-flanking sequence to the coding sequence of the simian virus 40 T-antigen develop spontaneous rhabdomyosarcomas of the right atria. The presence of the tumors is accompanied by dramatic elevations in plasma atrial natriuretic peptide (ANP) immunoreactivity (1,698 +/- 993 vs. 60 +/- 18 fmol/ml for controls) and hematocrit (56 +/- 8 vs. 51 +/- 2 for controls). The immunoreactive ANP (irANP) present in the tumors is similar in size to irANP found in normal mouse atria. ANP mRNA transcripts present in the tumors also appear to be very similar in overall size and 5'-termini to those produced in normal cardiac tissue. Microscopically, the tumors are composed of a disorganized array of densely packed abnormal-appearing cells. Immunocytochemistry and in situ hybridization analysis reveal considerable heterogeneity in ANP gene expression. ANP peptide and mRNA are detectable throughout the parenchyma of the tumors, but absolute levels of expression vary widely among different cells in the population. These tumors represent a potentially valuable model for the study of inappropriate ANP secretion and may provide a tissue source for the development of an ANP-producing atrial cell line.
authors.affiliation: Department of Medicine, University of California, San Francisco 94143.
authors.forename: D G
authors.initials: DG
authors.lastname: Gardner
authors.forename: M J
authors.initials: MJ
authors.lastname: Camargo
authors.forename: R R
authors.initials: RR
authors.lastname: Behringer
authors.forename: R L
authors.initials: RL
authors.lastname: Brinster
authors.forename: J D
authors.initials: JD
authors.lastname: Baxter
authors.forename: S A
authors.initials: SA
authors.lastname: Atlas
authors.forename: J H
authors.initials: JH
authors.lastname: Laragh
authors.forename: C F
authors.initials: CF
authors.lastname: Deschepper
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics; D002851:Chromatography, High Pressure Liquid; D015870:Gene Expression; D006325:Heart Atria; D006338:Heart Neoplasms / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D012313:RNA; D015347:RNA Probes; D018075:RNA, Complementary
chemical_list: D015347:RNA Probes; D018075:RNA, Complementary; D012313:RNA; D009320:Atrial Natriuretic Factor