title: Effects of immobilizations stress with or without water immersion on the expression of atrial natriuretic peptide in the hearts of two rat strains.
abstract: Atrial natriuretic peptide (ANP) is produced and released by mammalian cardiomyocytes and induces natriuresis, diuresis, and lowering of blood pressure. The present study examined localization of ANP and a possible role of the hypothalamic-pituitary-adrenal axis (HPA) activity on the expression of proANP gene in the heart. The Sprague Dawley (SD) and Lewis (LE) rat strains were used. The animals were exposed to the two types of stress: immobilization and immobilization combined with water immersion for 1 hour. Localization of ANP was detected by immunohistochemistry and expression of the proANP mRNA by real-time qPCR in all heart compartments of control and stressed animals after 1 and 3 hours after stress termination (IS1, IS3, ICS1, and ICS3). Relatively high density of ANP-immunoreactivity was observed in both atria of both rat strains. In control rats of both strains, the expression of the proANP mRNA was higher in the atria than in ventricles. In SD rats with the intact HPA axis, an upregulation of ANP gene expression was observed in the right atrium after IS1, in both atria and the left ventricle after IS3 and in the left atrium and the left ventricle after ICS3. In LE rats with a blunted reactivity of the HPA axis, no increase or even a downregulation of the gene expression was observed. Thus, acute stress-induced increase in the expression of the proANP gene is related to the activity of the HPA axis. It may have relevance to ANP-induced protection of the heart.
authors: Department of Physiology, Charles University in Prague, Faculty of Medicine in PilsenPilsen, Czech Republic; Biomedical Centre, Charles University in Prague, Faculty of Medicine in PilsenPilsen, Czech Republic.
authors: Jana
authors: J
authors: Slavikova
authors: Department of Physiology, Charles University in Prague, Faculty of Medicine in PilsenPilsen, Czech Republic; Biomedical Centre, Charles University in Prague, Faculty of Medicine in PilsenPilsen, Czech Republic.
authors: Eliska
authors: E
authors: Mistrova
authors: Institute of Medical Biochemistry and Laboratory Diagnostics, 1st Faculty of Medicine and General University Hospital, Charles University in Prague Prague, Czech Republic.
authors: Vera
authors: V
authors: Klenerova
authors: Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences Brno, Czech Republic.
authors: Peter
authors: P
authors: Kruzliak
authors: 2nd Department of Internal Medicine, Faculty of Medicine, Comenius University and University Hospital Bratislava, Slovakia.
authors: Martin
authors: M
authors: Caprnda
authors: Institute of Medical Biochemistry and Laboratory Diagnostics, 1st Faculty of Medicine and General University Hospital, Charles University in Prague Prague, Czech Republic.
authors: Sixtus
authors: S
authors: Hynie
authors: Institute of Medical Biochemistry and Laboratory Diagnostics, 1st Faculty of Medicine and General University Hospital, Charles University in Prague Prague, Czech Republic.
authors: Pavel
authors: P
authors: Sida
authors: Department of Physiology, Charles University in Prague, Faculty of Medicine in PilsenPilsen, Czech Republic; Biomedical Centre, Charles University in Prague, Faculty of Medicine in PilsenPilsen, Czech Republic.
authors: Magdalena Chottova
authors: MC
authors: Dvorakova
keywords: Atrial natriuretic peptide- stress- heart- real-time qPCR