Document Detail


Enhanced vasoconstrictor prostanoid production by sinusoidal endothelial cells increases portal perfusion pressure in cirrhotic rat livers.
MedLine Citation:
PMID:  17459512     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
BACKGROUND/AIMS: Cyclooxygenase-1 (COX-1) is overexpressed in sinusoidal endothelial cells (SEC) of cirrhotic rat livers, and through an enhanced production of vasoconstrictor prostanoids contributes to increase intrahepatic resistance. Our study was aimed at investigating the role of enhanced AA bioavailability modulating the hepatic vascular tone of cirrhotic livers and identifying which prostanoid is involved. METHODS: SEC isolated from control and cirrhotic rat livers were incubated with AA, methoxamine or vehicle. TXA(2) was quantified. In addition, portal perfusion pressure (PP) response curves to AA were performed in rat livers pre-incubated with vehicle, SC-560 (COX-1 inhibitor), Furegrelate (inhibitor of TXA(2) synthesis) and SQ-29548 (PGH(2)/TXA(2) receptor blocker). cPLA2 activity was determined in control and cirrhotic livers. RESULTS: AA and methoxamine incubation promoted a significant increase in TXA(2) release by Cirrhotic-SEC, but not in Control-SEC. AA produced a dose-dependent increase in the PP, associated with increased TXA(2) release. These responses were significantly greater in cirrhotic livers. COX-1 inhibition and PGH(2)/TXA(2) receptor blockade, but not TXA(2) synthase inhibition, markedly attenuated the PP response to AA of cirrhotic livers. Additionally, cirrhotic livers exhibited significantly increased cPLA2 activity. CONCLUSIONS: An enhanced production of vasoconstrictor prostanoids, probably PGH(2), by SEC contributes to increase vascular tone of cirrhotic livers.
Authors:
Jorge Gracia-Sancho; Bàrbara Laviña; Aina Rodríguez-Vilarrupla; Héctor García-Calderó; Jaime Bosch; Joan Carles García-Pagán
Publication Detail:
Type:  In Vitro; Journal Article; Research Support, Non-U.S. Gov't     Date:  2007-04-05
Journal Detail:
Title:  Journal of hepatology     Volume:  47     ISSN:  0168-8278     ISO Abbreviation:  J. Hepatol.     Publication Date:  2007 Aug 
Date Detail:
Created Date:  2007-07-10     Completed Date:  2007-10-18     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8503886     Medline TA:  J Hepatol     Country:  England    
Other Details:
Languages:  eng     Pagination:  220-7     Citation Subset:  IM    
Affiliation:
Hepatic Hemodynamic Laboratory, Liver Unit, IMDIM, Hospital Clínic, Ciberehd and Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona, Villarroel 170, 08036 Barcelona, Spain.
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MeSH Terms
Descriptor/Qualifier:
Animals
Arachidonic Acid / administration & dosage,  pharmacokinetics,  pharmacology
Biological Availability
Cyclooxygenase 1 / drug effects
Cyclooxygenase Inhibitors / pharmacology
Dose-Response Relationship, Drug
Endothelial Cells / metabolism*
Enzyme Inhibitors / pharmacology
Liver / blood supply*
Liver Cirrhosis / physiopathology*
Male
Perfusion
Phospholipases A / metabolism
Portal System / drug effects,  physiopathology*
Pressure
Prostaglandins / biosynthesis*
Rats
Rats, Wistar
Receptors, Thromboxane A2, Prostaglandin H2 / antagonists & inhibitors
Thromboxane B2 / biosynthesis
Thromboxane-A Synthase / antagonists & inhibitors
Vasoconstriction
Vasoconstrictor Agents / metabolism*
Chemical
Reg. No./Substance:
0/Cyclooxygenase Inhibitors; 0/Enzyme Inhibitors; 0/Prostaglandins; 0/Receptors, Thromboxane A2, Prostaglandin H2; 0/Vasoconstrictor Agents; 506-32-1/Arachidonic Acid; 54397-85-2/Thromboxane B2; EC 1.14.99.1/Cyclooxygenase 1; EC 3.1.1.-/Phospholipases A; EC 5.3.99.5/Thromboxane-A Synthase

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