Document Detail


Luminal endothelial lectins with affinity for N-acetylglucosamine determine flow-induced cardiac and vascular paracrine-dependent responses.
MedLine Citation:
PMID:  20562333     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Coronary blood flow applied to the endothelial lumen modulates parenchymal functions via paracrine effectors, but the mechanism of flow sensation is unknown. We and others have demonstrated that coronary endothelial luminal membrane (CELM) oligosaccharides and lectins are involved in flow detection, and we proposed that cardiac effects of coronary flow result from a reversible flow-modulated lectin-oligosaccharide interaction. Recently, glycosylated and amiloride-sensitive Na(+)/Ca(++) channels (ENaCs) have been proposed to be involved in the flow-induced endothelial responses. Because N-acetylglucosamine (GlcNac) is one of the main components of glycocalyx oligosaccharides (i.e., hyaluronan [-4GlcUAbeta1-3GlcNAcbeta1-](n)), the aim of this article is to isolate and define CELM GlcNac-binding lectins and determine their role in cardiac and vascular flow-induced effects. For this purpose, we synthesized a 460-kDa GlcNac polymer (GlcNac-Pol) with high affinity toward GlcNac-recognizing lectins. In the heart, intracoronary administration of GlcNac-Pol upon binding to CELM diminishes the flow-dependent positive inotropic and dromotropic effects. Furthermore, GlcNac-Pol was used as an affinity probe to isolate CELM GlcNac-Pol-recognizing lectins and at least 35 individual lectinic peptides were identified, one of them the beta-ENaC channel. Some of these lectins could participate in flow sensing and in GlcNac-Pol-induced effects. We also adopted a flow-responsive and well-accepted model of endothelial-parenchymal paracrine interaction: isolated blood vessels perfused at controlled flow rates. We established that flow-induced vasodilatation (FIV) is blocked by endothelial luminal membrane (ELM) bound GlcNac-Pol, nitro-l-arginine methyl ester and indomethacin, amiloride, and hyaluronidase. The effect of hyaluronidase was reversed by infusion of soluble hyaluronan. These results indicate that GlcNac-Pol inhibits FIV by competing and displacing intrinsic hyaluronan bound to a lectinic structure such as the amiloride-sensitive ENaC. Nitric oxide and prostaglandins are the putative paracrine mediators of FIV.
Authors:
Juan Ramiro-Diaz; Alma Barajas-Espinosa; Erika Chi-Ahumada; Sandra Perez-Aguilar; David Torres-Tirado; Jesus Castillo-Hernandez; Maureen Knabb; Ana Barba de Rosa; Rafael Rubio
Related Documents :
6997983 - Model system for the study of inital damage to arterial endothelial cells in situ by sc...
6660303 - Microvascular blood flow: evidence indicating a cubic dependence on arteriolar diameter.
2981933 - Effects of synthetic leukotrienes on local blood flow and vascular permeability in porc...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2010-06-18
Journal Detail:
Title:  American journal of physiology. Heart and circulatory physiology     Volume:  299     ISSN:  1522-1539     ISO Abbreviation:  Am. J. Physiol. Heart Circ. Physiol.     Publication Date:  2010 Sep 
Date Detail:
Created Date:  2010-08-31     Completed Date:  2010-09-22     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  100901228     Medline TA:  Am J Physiol Heart Circ Physiol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  H743-51     Citation Subset:  IM    
Affiliation:
Departamento de Fisiologia, Universidad Autonoma de San Luis Potosi, San Luis Potosi, Mexico.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Acetylglucosamine / metabolism*
Animals
Chromatography, Affinity
Coronary Circulation / physiology*
Endothelium, Vascular / physiology*
Guinea Pigs
Lectins / metabolism*
Male
Myocardial Contraction / physiology
Myocardium / metabolism*
Vasodilation / physiology
Chemical
Reg. No./Substance:
0/Lectins; 7512-17-6/Acetylglucosamine

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  The number of cytomegalovirus-specific CD4+ T cells is markedly expanded in patients with B-cell chr...
Next Document:  Decreased left ventricular distensibility in response to postural change in older patients with hear...