• Cardiac adaptation to hypertension in adult female Dahl salt-sensitive rats is dependent on ovarian function, but loss of ovarian function does not predict early maladaptation 

      Ludvigsen, Stian; Mancusi, Costantino; Kildal, Simon; de Simone, Giovanni; Gerdts, Eva; Ytrehus, Kirsti (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-02-08)
      Aim of study was to examine experimentally the adult female hypertensive heart in order to determine the role of ovary function in the response of the heart to salt-dependent hypertension. Dahl salt-sensitive rats, age 12 weeks, with/without ovariectomy were fed a standard (0.3% NaCl) or high-salt diet (8%) for 16 weeks. Mean arterial blood pressure monitored noninvasively in conscious state ...
    • Coronary flow reserve in pregnant rats with increased left ventricular afterload 

      Songstad, Nils Thomas; Serrano, Maria; Sitras, Vasilis; Johansen, David; Ytrehus, Kirsti; Acharya, Ganesh (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-07-09)
      Background Coronary flow reserve (CFR) is used as a measure of coronary endothelial function. We investigated the effect of increased afterload on CFR of pregnant and non-pregnant rats. Methods Afterload increase in Wister rats (both pregnant and non-pregnant) was achieved by the infusion of angiotensin II (Ang II) for ~10 days or by subjecting them to transverse aortic constriction (TAC) ...
    • ESC working group on cellular biology of the heart: Position paper for Cardiovascular Research: Tissue engineering strategies combined with cell therapies for cardiac repair in ischaemic heart disease and heart failure 

      Madonna, Rosalinda; Van Laake, Linda W.; Bøtker, Hans Erik; Davidson, Sean M.; De Caterina, Raffaele; Engel, Felix B.; Eschenhagen, Thomas; Fernandez-Aviles, Francesco; Hausenloy, Derek J.; Hulot, Jean-Sebastien; Lecour, Sandrine; Leor, Jonathan; Menasché, Philippe; Pesce, Maurizio; Perrino, Cinzia; Prunier, Fabrice; Van Linthout, Sophie; Ytrehus, Kirsti; Zimmermann, Wolfram-Hubertus; Ferdinandy, Péter; Sluijter, Joost P.G. (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-01-17)
      Morbidity and mortality from ischaemic heart disease (IHD) and heart failure (HF) remain significant in Europe and are increasing worldwide. Patients with IHD or HF might benefit from novel therapeutic strategies, such as cellbased therapies. We recently discussed the therapeutic potential of cell-based therapies and provided recommendations on how to improve the therapeutic translation of these ...
    • Extracellular vesicles in diagnostics and therapy of the ischaemic heart: Position Paper from the Working Group on Cellular Biology of the Heart of the European Society of Cardiology 

      Sluijter, Joost Petrus Geradus; Davidson, Sean Michael; Boulanger, Chantal M; Buzas, Edit Iren; De Kleijn, Dominique P.V.; Engel, Felix Benedikt; Giricz, Zoltán; Hausenloy, Derek J.; Kishore, Raj; Lecour, Sandrine; Leor, Jonathan; Madonna, Rosalinda; Perrino, Cinzia; Prunier, Fabrice; Sahoo, Susmita; Schiffelers, Ray Michel; Schulz, Rainer; Van Laake, Linda Wilhelmina; Ytrehus, Kirsti; Ferdinandy, Péter (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-02)
      Extracellular vesicles (EVs)—particularly exosomes and microvesicles (MVs)—are attracting considerable interest in the cardiovascular field as the wide range of their functions is recognized. These capabilities include transporting regulatory molecules including different RNA species, lipids, and proteins through the extracellular space including blood and delivering these cargos to recipient ...
    • Gene expression, function and ischemia tolerance in male and female rat hearts after sub-toxic levels of Angiotensin II 

      Aljabri, Mohammad Belal; Lund, Trine; Høper, Anje Christina; Andreasen, Thomas Vennø; Al-Saad, Samer; Lindal, Sigurd; Ytrehus, Kirsti (Journal article; Tidsskriftartikkel; Peer reviewed, 2010)
    • Gene Expression, Function and Ischemia Tolerance in Male and Female Rat Hearts After Sub-Toxic Levels of Angiotensin II 

      Aljabri, Mohammad Belal; Lund, trine; Høper, Anje Christina; Andreasen, thomas vennØ; Al-Saad, Samer; Lindal, Sigurd; Ytrehus, Kirsti (Journal article; Tidsskriftartikkel; Peer reviewed, 2010-12-19)
      To examine the response to chronic high-dose angiotensin II (Ang II) and a proposed milder response in female hearts with respect to gene expression and ischemic injury. Female and male litter–matched rats were treated with 400 ng kg<sup>-1</sup> min<sup>-1</sup> Ang II for 14 days. Hearts were isolated, subjected to 30-min ischemia and 30-min reperfusion in combination with functional monitoring ...
    • Heart Angiotensin- Converting Enzyme and Angiotensin-Converting Enzyme 2 Gene Expression Associated With Male Sex and Salt-Sensitive Hypertension in the Dahl Rat. 

      Ytrehus, Kirsti; Gerdts, Eva; Mancusi, Costatino; de Simone, Giovanni; Ludvigsen, Stian (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-19)
      Angiotensin-converting enzyme 2 (ACE 2) in the heart including its sex dependency in the hypertensive heart, has not been much studied compared to ACE. In the present study, we used the Dahl salt-sensitive rat exposed to fructose and salt to model a hypertensive phenotype in males, females, and ovariectomized females. Blood pressure was measured by the tale-cuff technique in the conscious state. ...
    • Heart Angiotensin-Converting Enzyme and Angiotensin-Converting Enzyme 2 Gene Expression Associated With Male Sex and Salt-Sensitive Hypertension in the Dahl Rat 

      Ytrehus, Kirsti; Ludvigsen, Stian; Mancusi, Costantino; Gerdts, Eva; de Simone, Giovanni (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-19)
      Angiotensin-converting enzyme 2 (ACE 2) in the heart including its sex dependency in the hypertensive heart, has not been much studied compared to ACE. In the present study, we used the Dahl salt-sensitive rat exposed to fructose and salt to model a hypertensive phenotype in males, females, and ovariectomized females. Blood pressure was measured by the tale-cuff technique in the conscious state. ...
    • Human concentrations of uric acid scavenges adaptive and maladaptive ROS in isolated rat hearts subjected to ischemic stress 

      Boardman, Neoma Tove; Falck, Aleksander Tank; Lund, Trine; Chu, X; Martin, Armas Maria Montserrat; Norvik, Jon Viljar; Jenssen, Trond Geir; Ytrehus, Kirsti (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-09-14)
      Uric acid is a purine degradation product but also an important antioxidant and ROS scavenger. Experimental settings that mimic myocardial ischemia-reperfusion have not included uric acid despite that it is always present in human extracellular fluid and plasma. We hypothesized that uric acid has an important role in myocardial ROS scavenging. Here, we tested the cardiac response to uric acid on ...
    • Impact of maturation on myocardial response to ischemia and the effectiveness of remote preconditioning in male rats 

      Kindernay, Lucia; Farkasova, Veronika; Neckar, Jan; Hrdlicka, Jaroslav; Ytrehus, Kirsti; Ravingerova, Tanya (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-12)
      Aging attenuates cardiac tolerance to ischemia/reperfusion (I/R) associated with defects in protective cell signaling, however, the onset of this phenotype has not been completely investigated. This study aimed to compare changes in response to I/R and the effects of remote ischemic preconditioning (RIPC) in the hearts of younger adult (3 months) and mature adult (6 months) male Wistar rats, with ...
    • Improving translational research in sex-specific effects of comorbidities and risk factors in ischaemic heart disease and cardioprotection: Position paper and recommendations of the ESC Working Group on Cellular Biology of the Heart 

      Perrino, Cinzia; Ferdinandy, Péter; Bøtker, Hans Erik; Brundel, Bianca J. J. M; Collins, Peter; Davidson, Sean M; Den Ruijter, Hester M.; Engel, Felix B.; Gerdts, Eva; Girao, Henrique; Gyöngyösi, Mariann; Hausenloy, Derek J.; Lecour, Sandrine; Madonna, Rosalinda; Marber, Michael; Murphy, Elizabeth; Pesce, Maurizio; Regitz-Zagrosek, Vera; Sluijter, Joost P.G.; Steffens, Sabine; Gollmann-Tepeköylü, Can; Van Laake, Linda W.; Van Linthout, Sophie; Schulz, Rainer; Ytrehus, Kirsti (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-06-02)
      Ischaemic heart disease (IHD) is a complex disorder and a leading cause of death and morbidity in both men and women. Sex, however, affects several aspects of IHD, including pathophysiology, incidence, clinical presentation, diagnosis as well as treatment and outcome. Several diseases or risk factors frequently associated with IHD can modify cellular signalling cascades, thus affecting ischaemia/reperfusion ...
    • Low adiponectin is associated with diastolic dysfunction in women: A cross-sectional study from the Tromsø Study 

      Norvik, Jon Viljar; Schirmer, Henrik; Ytrehus, Kirsti; Jenssen, Trond Geir; Zykova, Svetlana; Eggen, Anne Elise; Eriksen, Bjørn Odvar; Solbu, Marit Dahl (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-03-14)
      Background: Heart failure with preserved ejection fraction is closely associated with diastolic dysfunction and related to obesity and female sex. We investigated whether adiponectin, an adipocyte-secreted protein hormone with cardioprotective effects, was associated with indices of diastolic dysfunction, and whether the association was sex dependent. <br>Methods: We conducted a cross-sectional ...
    • Overweight modifies the longitudinal association between uric acid and some components of the metabolic syndrome: The Tromsø Study 

      Norvik, Jon Viljar; Storhaug, Hilde-Merete; Ytrehus, Kirsti; Jenssen, Trond Geir; Zykova, Svetlana; Eriksen, Bjørn Odvar; Solbu, Marit Dahl (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-05-10)
      Background: Elevated uric acid (UA) is associated with the presence of the metabolic syndrome (MetS). In a prospective cohort study, we assessed whether baseline and longitudinal change in UA were risk factors for development of MetS and its individual components. <br> Methods: We included 3087 women and 2996 men who had UA measured in the population based Tromsø Study 1994–95. The participants ...
    • Recombinant human activated protein C attenuates endotoxin-induced lung injury in awake sheep 

      Langbakk, Bodil; Wærhaug, Kristine; Kuklin, Vladimir N.; Kirov, Mikhail Y.; Sovershaev, Mikhail; Ingebretsen, Ole C.; Ytrehus, Kirsti; Bjertnæs, Lars J. (Journal article; Tidsskriftartikkel; Peer reviewed, 2008-08-15)
      Introduction: Acute lung injury often complicates severe sepsis. In Gram-negative sepsis, bacterial endotoxin activates both coagulation and inflammation. Enhanced lung vascular pressures and permeability, increased extravascular lung water content and deteriorated gas exchange characterize ovine endotoxin-induced lung injury, a frequently used model of acute lung injury. Recombinant human ...
    • The role of mitochondrial reactive oxygen species, NO and H2S in ischaemia/reperfusion injury and cardioprotection 

      Andreadou, Ioanna; Schulz, Rainer; Papapetropoulos, Andreas; Turan, Belma; Ytrehus, Kirsti; Ferdinandy, Peter; Daiber, Andreas; Di Lisa, Fabio (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-08)
      Redox signalling in mitochondria plays an important role in myocardial ischaemia/reperfusion (I/R) injury and in cardioprotection. Reactive oxygen and nitrogen species (ROS/RNS) modify cellular structures and functions by means of covalent changes in proteins including among others S‐nitros(yl)ation by nitric oxide (NO) and its derivatives, and S‐sulphydration by hydrogen sulphide (H<sub>2</sub>S). ...
    • Tezosentan reduces the microvascular filtration coefficient in isolated lungs from rats subjected to cecum ligation and puncture 

      Kuklin, Vladimir N.; Sovershaev, Mikhail; Andreasen, Thomas; Skogen, Vegard; Ytrehus, Kirsti; Bjertnæs, Lars J. (Journal article; Tidsskriftartikkel; Peer reviewed, 2005-10-18)
      Introduction: We recently demonstrated that the non-selective endothelin-1 (ET-1) receptor blocker tezosentan antagonizes ovine acute lung injury (ALI) following infusion of endotoxin or ET-1 by reducing the enhanced lung microvascular pressure, although we could not exclude the possibility of a simultaneous decline in microvascular permeability. In the present study, our aim was to find out if ...
    • Tezosentan-induced attenuation of lung injury in endotoxemic sheep is associated with reduced activation of protein kinase C 

      Ingebretsen, Ole C.; Kuklin, Vladimir N.; Kirov, Mikhail Y.; Sovershaev, Mikhail; Andreasen, Thomas; Ytrehus, Kirsti; Bjertnæs, Lars J. (Journal article; Tidsskriftartikkel; Peer reviewed, 2005-03-04)
      Introduction: Studies in vitro reveal that endothelin-1 (ET-1) activates the α isoform of protein kinase C (PKC-α) in cultures of endothelial cells, thereby deranging cellular integrity. Sepsis and endotoxemia are associated with increased plasma concentrations of ET-1 that induce acute lung injury (ALI). We recently reported that non-selective ET-1 receptor blockade attenuates ALI in sheep by ...