Mesenteric arteries responsiveness to acute variations of wall shear stress is impaired in rats with liver cirrhosis.
Summary of "Mesenteric arteries responsiveness to acute variations of wall shear stress is impaired in rats with liver cirrhosis."
Abstract Objective. In liver cirrhosis, excessive splanchnic vasodilation is due to abnormal synthesis of endogenous vasodilators and to decreased sensitivity to vasoconstrictors. The role of mechanical stimuli such as wall shear stress (WSS) on splanchnic circulation remains unclear. The aim of this study was to assess the vasodilation induced by wall shear stress (WSS) and acute changes in blood flow in the mesenteric arteries in an experimental model of liver cirrhosis. Materials and Methods. The effect of acute changes in intraluminal flow (0, 10, and 20 μl/min) and WSS on the diameter of the mesenteric arteries (diameters <500 μm) of control and cirrhotic rats was assessed, at baseline and after the inhibition of nitric oxide synthase, cyclooxygenase and hemeoxygenase. Concentration-response curves to phenylephrine were also obtained. Results. In controls, the increase in intraluminal flow led to a significant increase in arterial diameter (p < 0.05), while WSS remained stable; the effect was maintained in vessels pre-constricted with phenylephrine, blocked by the exposure to indomethacin and L-NAME and restored by the subsequent addition of chromium mesoporphyrin (p < 0.05). In cirrhotic arteries, arterial diameters did not change in response to acute increase in flow, neither at baseline nor after exposure to indomethacin and L-NAME, while WSS increased (p < 0.01). Responsiveness to flow was partially restored (p < 0.05) after exposure of the arteries to chromium mesoporphyrin in addition to indomethacin and L-NAME. Conclusions. Arteries from cirrhotic rats showed an abolished responsiveness to acute variations in flow, which exposes the mesenteric endothelium to sudden variations in WSS.
Affiliation
Clinica Medica 5, Department of Clinical and Experimental Medicine, University of Padova , Padova , Italy.
Journal Details
This article was published in the following journal.
Name: Scandinavian journal of gastroenterology
ISSN: 1502-7708
Pages:
Links
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/22774919
- DOI: http://dx.doi.org/10.3109/00365521.2012.703231
Medical and Biotech [MESH] Definitions
Mesenteric Arteries
Arteries which arise from the abdominal aorta and distribute to most of the intestines.
Mesenteric Artery, Inferior
The artery supplying nearly all the left half of the transverse colon, the whole of the descending colon, the sigmoid colon, and the greater part of the rectum. It is smaller than the superior mesenteric artery (MESENTERIC ARTERY, SUPERIOR) and arises from the aorta above its bifurcation into the common iliac arteries.
Thoracic Arteries
Arteries originating from the subclavian or axillary arteries and distributing to the anterior thoracic wall, mediastinal structures, diaphragm, pectoral muscles, mammary gland and the axillary aspect of the chest wall.
Mammary Arteries
Arteries originating from the subclavian or axillary arteries and distributing to the anterior thoracic wall, mediastinal structures, diaphragm, pectoral muscles and mammary gland.
Viscosity
The resistance that a gaseous or liquid system offers to flow when it is subjected to shear stress. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
PubMed Articles
Human common carotid wall shear stress as a function of age and gender: a 12-year follow-up study.
Hemodynamic forces play a role in the development of atherosclerosis. Their variations with age have been assessed in cross-sectional, but not longitudinal, studies. The aim of the present study was t...
Increased sympathetic nervous system (SNS) activity, testosterone, and spontaneously hypertensive rat Y chromosome (SHR Yc) play a role in a genetic model of hypertension. Male rats with the SHR Yc an...
BACKGROUND: -To analyze the in-vivo distribution of absolute wall shear stress (WSS(abs)) and oscillatory shear index (OSI) in the carotid bifurcation and to evaluate its dependence on bifurcation geo...
Pathologies of the aortic valve such as aortic sclerosis are thought to impact coronary blood flow. Recent clinical investigations have observed simultaneous structural and hemodynamic variations in t...
Wall shear over high degree stenoses pertinent to atherothrombosis.
Atherothrombosis can induce acute myocardial infarction and stroke by progressive stenosis of a blood vessel lumen to full occlusion. Since thrombus formation and embolization may be shear-dependent,...
Clinical Trials
Pilot Study on Shear-induced Platelet Aggregation in Acute Coronary Syndromes
The purpose of this study is to determine whether shear-induced platelet aggregation is able to discriminate first acute coronary syndrome (ACS) from recurrent ACS
Shear and Pressure Reducing Insoles for the Diabetic Foot
We evaluated the feasibility of the GlideSoft™ novel insole to reduce pressure and shear forces on the foot. No commercially available insoles are designed to reduce shear. Although insu...
The Importance of Glucagon-Like Peptide-2 (GLP-2)in Mesenteric Bloodflow in Humans
The purpose of this study is to study the effect of GLP-2 on mesenteric bloodflow in healthy adults by the use of ultrasound., it is the hypothesis that GLP-2 vil increase the bloodflow.
Magnetic Resonance Imaging of the Coronary Vessel Wall
Despite advances in prevention and treatment, clinical manifestations of atherosclerosis (e.g. myocardial infarction, stroke) remain the largest cause of mortality in the Western world. Th...
There are naturally occuring variations in the genetic makeup of all of us. Some of these variations may contribute to a change in susceptibility toward different diseases or change the pr...
