title: Expression of V-1, a novel catecholamine biosynthesis regulatory protein, is enhanced by hypertension in atrial myocytes of Dahl salt-sensitive rats.
abstract: V-1 positively controls catecholamine synthetic gene transcription to promote catecholamine production in PC12D cells. In this study, immunohistochemical analysis revealed that in Wistar rats, V-1 immunoreactivity was localized not only in sympathetic axons but also in the cytoplasm of cardiomyocytes, and that the immunoreactivity in atrial myocytes was more intense than that in ventricular myocytes. Western blot analysis also showed that V-1 expression level in the atrium was higher than that in the ventricle of Wistar rat hearts. When Dahl salt-sensitive (DS) rats were fed an 8% NaCl diet after the age of 6 weeks, blood pressure was raised 230mm Hg at 18 weeks. V-1 expression was shown to be increased in the atrial myocytes of these DS rats, but not in the sympathetic axons, when assayed by immunohistochemistry. These results suggest that in normotensive rats, V-1 is preferentially expressed in the cytoplasm of cardiomyocytes in the atrium rather than in the ventricle. It is also suggested that V-1 expression is increased by hypertension in DS rat atrium.
authors.affiliation: Department of Pharmaceutical Molecular Biology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan. yamakuni@mail.pharm.tohoku.ac.jp
authors.forename: Tohru
authors.initials: T
authors.lastname: Yamakuni
authors.forename: Michio
authors.initials: M
authors.lastname: Hashimoto
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Sakagami
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Masumi
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Fujii
authors.forename: Hideko
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Dileep Kumar
authors.initials: DK
authors.lastname: Rohra
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Hiwatashi
authors.forename: Takao
authors.initials: T
authors.lastname: Honma
authors.forename: Hisatake
authors.initials: H
authors.lastname: Kondo
authors.forename: Osamu
authors.initials: O
authors.lastname: Shido
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ohizumi
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002395:Catecholamines / Q000096:biosynthesis; D003600:Cytosol / Q000378:metabolism; D015870:Gene Expression; D006325:Heart Atria / Q000378:metabolism; D006352:Heart Ventricles / Q000378:metabolism; D006973:Hypertension / Q000235:genetics / Q000378:metabolism*; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins; D009206:Myocardium / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D020303:Rats, Inbred Dahl; D017208:Rats, Wistar; D012982:Sodium, Dietary / Q000008:administration & dosage
chemical_list: D002395:Catecholamines; D036341:Intercellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D012982:Sodium, Dietary; C065700:myotrophin