Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2007-7-19
pubmed:abstractText
The renin-angiotensin-aldosterone system contributes to cardiac remodeling, hypertrophy, and left ventricular dysfunction. Angiotensin II and aldosterone (corticosterone in rodents) together generate reactive oxygen species (ROS) via reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, which likely facilitate this hypertrophy and remodeling. This investigation sought to determine whether cardiac oxidative stress and cellular remodeling could be attenuated by in vivo mineralocorticoid receptor (MR) blockade in a rodent model of the chronically elevated tissue renin-angiotensin-aldosterone system, the transgenic TG (mRen2) 27 rat (Ren2). The Ren2 overexpresses the mouse renin transgene with resultant hypertension, insulin resistance, proteinuria, and cardiovascular damage. Young (6- to 7-wk-old) male Ren2 and age-matched Sprague-Dawley rats were treated with spironolactone or placebo for 3 wk. Heart tissue ROS, immunohistochemical analysis of 3-nitrotyrosine, and NADPH oxidase (NOX) subunits (gp91(phox) recently renamed NOX2, p22(phox), Rac1, NOX1, and NOX4) were measured. Structural changes were assessed with cine-magnetic resonance imaging, transmission electron microscopy, and light microscopy. Significant increases in Ren2 septal wall thickness (cine-magnetic resonance imaging) were accompanied by perivascular fibrosis, increased mitochondria, and other ultrastructural changes visible by light microscopy and transmission electron microscopy. Although there was no significant reduction in systolic blood pressure, significant improvements were seen with MR blockade on ROS formation and NOX subunits (each P < 0.05). Collectively, these data suggest that MR blockade, independent of systolic blood pressure reduction, improves cardiac oxidative stress-induced structural and functional changes, which are driven, in part, by angiotensin type 1 receptor-mediated increases in NOX.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0013-7227
pubmed:author
pubmed:issnType
Print
pubmed:volume
148
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3773-80
pubmed:dateRevised
2007-12-3
pubmed:meshHeading
pubmed-meshheading:17494996-Aldosterone Antagonists, pubmed-meshheading:17494996-Animals, pubmed-meshheading:17494996-Animals, Genetically Modified, pubmed-meshheading:17494996-Blood Pressure, pubmed-meshheading:17494996-Cardiomegaly, pubmed-meshheading:17494996-Chronic Disease, pubmed-meshheading:17494996-Fibrosis, pubmed-meshheading:17494996-Magnetic Resonance Imaging, pubmed-meshheading:17494996-Male, pubmed-meshheading:17494996-Microscopy, Electron, Transmission, pubmed-meshheading:17494996-Mitochondria, pubmed-meshheading:17494996-Myocardium, pubmed-meshheading:17494996-Myocytes, Cardiac, pubmed-meshheading:17494996-NADPH Oxidase, pubmed-meshheading:17494996-Oxidative Stress, pubmed-meshheading:17494996-Rats, pubmed-meshheading:17494996-Rats, Sprague-Dawley, pubmed-meshheading:17494996-Receptors, Mineralocorticoid, pubmed-meshheading:17494996-Renin, pubmed-meshheading:17494996-Renin-Angiotensin System, pubmed-meshheading:17494996-Spironolactone, pubmed-meshheading:17494996-Ventricular Dysfunction, Left, pubmed-meshheading:17494996-Ventricular Remodeling
pubmed:year
2007
pubmed:articleTitle
Mineralocorticoid receptor blockade attenuates chronic overexpression of the renin-angiotensin-aldosterone system stimulation of reduced nicotinamide adenine dinucleotide phosphate oxidase and cardiac remodeling.
pubmed:affiliation
Division of Endocrinology, University of Missouri School of Medicine, Columbia, Missouri 65212, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, N.I.H., Extramural