title: Genetic analysis of salt-sensitive hypertension in Dahl rats reveals a link between cardiac fibrosis and high cholesterol.
abstract: OBJECTIVE
  Previously we confirmed an important role of rat chromosome 19 (RNO19) for salt-sensitive hypertension and target organ damage in male Dahl salt-sensitive rats (SS rats). The aim of this study was to further analyse the basis of left ventricular (LV) fibrosis development in both male and female rats in this model. To this end we utilized a consomic SS-19(SHR) rat strain in which RNO19 was transferred from spontaneously hypertensive rats (SHR) into the susceptible background of SS.
  
  
  RESULTS
  We compared the effects of low- (0.2% NaCl) and high-salt (4% NaCl) diet on the development of hypertension, blood lipids and LV fibrosis in male and female SS, SHR, and SS-19(SHR) rats. Systolic blood pressure was significantly lower in male and female SS-19(SHR) compared with SS under both diets (P < 0.001). Relative LV weight was similarly reduced in SS-19(SHR) compared with SS in either sex. Plasma cholesterol concentrations were significantly elevated in high-salt fed male and female SS (141 +/- 6 and 110 +/- 7 mg/dL) compared with SHR (47 +/- 2 and 62 +/- 8 mg/dL, P < 0.001) and were significantly lowered in male and female consomic rats (100 +/- 7 and 87 +/- 3 mg/dL). Both LV interstitial fibrosis (LVIF) and perivascular fibrosis (LVPF) were significantly reduced in high-salt male and female SS-19(SHR). A significant correlation between cholesterol concentrations and LVPF (r = 0.464) and LVIF (r = 0.401, P < 0.0001, respectively) was detected. Fibrosis parameters demonstrated no correlation with blood pressure, LV weight or plasma triglycerides concentrations. LV immunohistochemistry analysis showed a significant higher number of ED-1 positive cells in SS compared with SS-19(SHR). Depositions of collagen I and fibronectin were also greater in LV tissue of SS compared with SS-19(SHR).
  
  
  CONCLUSIONS
  Our findings point to a link between hypercholesterolemia and LV fibrosis in salt-sensitive hypertension of SS rats which is genetically modulated by RNO19.
authors.affiliation: Department of Clinical Pharmacology and Toxicology CBF/CCM, CharitéCentrum für Therapieforschung, Charité - Universitätsmedizin Berlin, Berlin, Germany. norbert.wendt@charite.de
authors.forename: Norbert
authors.initials: N
authors.lastname: Wendt
authors.forename: Angela
authors.initials: A
authors.lastname: Schulz
authors.forename: Fatimunnisa
authors.initials: F
authors.lastname: Qadri
authors.forename: Juliane
authors.initials: J
authors.lastname: Bolbrinker
authors.forename: Peter
authors.initials: P
authors.lastname: Kossmehl
authors.forename: Karl
authors.initials: K
authors.lastname: Winkler
authors.forename: Monika
authors.initials: M
authors.lastname: Stoll
authors.forename: Roland
authors.initials: R
authors.lastname: Vetter
authors.forename: Reinhold
authors.initials: R
authors.lastname: Kreutz
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000235:genetics*; D002784:Cholesterol / Q000097:blood*; D024042:Collagen Type I / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D005353:Fibronectins / Q000378:metabolism; D005355:Fibrosis; D020022:Genetic Predisposition to Disease; D006937:Hypercholesterolemia / Q000097:blood / Q000235:genetics* / Q000473:pathology / Q000503:physiopathology; D006973:Hypertension / Q000097:blood / Q000235:genetics* / Q000473:pathology / Q000503:physiopathology; D008297:Male; D009206:Myocardium / Q000378:metabolism / Q000473:pathology*; D010641:Phenotype; D040641:Quantitative Trait Loci; D051381:Rats; D020303:Rats, Inbred Dahl; D011918:Rats, Inbred SHR; D055647:Rats, Transgenic; D012737:Sex Factors; D017673:Sodium Chloride, Dietary / Q000009:adverse effects; D015854:Up-Regulation; D018487:Ventricular Dysfunction, Left / Q000097:blood / Q000235:genetics* / Q000473:pathology / Q000503:physiopathology
chemical_list: D024042:Collagen Type I; D005353:Fibronectins; D017673:Sodium Chloride, Dietary; D002784:Cholesterol