Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2001-9-19
pubmed:abstractText
Anew model of thrombotic microangiopathy (TMA) was previously developed, and it was demonstrated that endothelial nitric oxide (NO) synthase (NOS) is upregulated in glomeruli in this model. It was hypothesized that the synthesis of NO, a potent vasodilator and platelet inhibitory factor, is induced as a defense mechanism. The goal of this study was to clarify the role of NO in this model. Ex vivo experiments using Western blotting and functional assays demonstrated upregulation of endothelial NOS in isolated glomeruli from TMA rats. In in vivo experiments, five groups of rats were studied, including rats with TMA treated with vehicle, N(G)-nitro-L-arginine methyl ester (L-NAME) (a NOS inhibitor), or L-N(6)-(1-iminoethyl)lysine (L-NIL) (a specific inducible NOS inhibitor) and normal control rats treated with vehicle or L-NAME. Blood urea nitrogen levels, BP, urinary nitrate/nitrite excretion, and proteinuria were measured. Histologic assessments using periodic acid-Schiff staining and immunohistologic studies with markers for endothelium, platelets, fibrin, cell proliferation, and apoptosis were also performed. L-NAME inhibition of NO synthesis in rats with TMA resulted in more severe glomerular and tubulointerstitial injury, which was accompanied by thrombus formation and a marked loss of endothelial cells, with more apoptotic cells. These changes were associated with severe renal function deterioration. In contrast, these features were less pronounced in the vehicle- or L-NIL-treated rats with TMA and were absent in the control animals. In conclusion, inhibition of NO production in this model of TMA markedly exacerbated renal injury. The absence of effects with L-NIL treatment suggests a minor role for inducible NOS in this model. These results suggest that production of NO, most likely by endothelial cells, is an important protective mechanism in TMA.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1046-6673
pubmed:author
pubmed:issnType
Print
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2088-97
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:11562407-Animals, pubmed-meshheading:11562407-Apoptosis, pubmed-meshheading:11562407-Blood Pressure, pubmed-meshheading:11562407-Blotting, Western, pubmed-meshheading:11562407-Cell Division, pubmed-meshheading:11562407-Endothelium, Vascular, pubmed-meshheading:11562407-Enzyme Inhibitors, pubmed-meshheading:11562407-Immunoglobulin G, pubmed-meshheading:11562407-Kidney, pubmed-meshheading:11562407-Kidney Glomerulus, pubmed-meshheading:11562407-Male, pubmed-meshheading:11562407-Microcirculation, pubmed-meshheading:11562407-NG-Nitroarginine Methyl Ester, pubmed-meshheading:11562407-Nitrates, pubmed-meshheading:11562407-Nitric Oxide, pubmed-meshheading:11562407-Nitric Oxide Synthase, pubmed-meshheading:11562407-Nitrites, pubmed-meshheading:11562407-Rats, pubmed-meshheading:11562407-Rats, Wistar, pubmed-meshheading:11562407-Renal Circulation, pubmed-meshheading:11562407-Severity of Illness Index, pubmed-meshheading:11562407-Thrombosis
pubmed:year
2001
pubmed:articleTitle
Protective role of nitric oxide in a model of thrombotic microangiopathy in rats.
pubmed:affiliation
Division of Nephrology and Endocrinology, University of Tokyo School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't