Abstract | BACKGROUND/AIMS: METHODS: In study 1, NO synthase activities were measured by the conversion of L-arginine to citrulline in tissues from portal-hypertensive, cirrhotic, and sham-operated rats and from normal rats pretreated with endotoxin and after long-term administration of dexamethasone, which inhibits the expression of inducible NO synthase. In study 2, systemic and splanchnic hemodynamics (radiolabeled microspheres) and gastric blood flow ( hydrogen gas clearance and reflectance spectrophotometry) were measured in portal-hypertensive rats after long-term administration of dexamethasone (0.25 mg.kg-1.day-1) or vehicle. RESULTS: In study 1, constitutive and inducible NO synthase activities in portal-hypertensive or cirrhotic rats were similar to those observed in sham-operated rats. The significant increase in the inducible activity observed after endotoxin injection was prevented when rats received long-term treatment with dexamethasone. In study 2, cardiac index, portal-pressure, portal venous inflow, and gastric blood flow were similar in dexamethasone-or vehicle-treated portal-hypertensive rats. CONCLUSIONS:
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Authors | M Fernández, J C García-Pagán, M Casadevall, C Bernadich, C Piera, B J Whittle, J M Piqué, J Bosch, J Rodés |
Journal | Gastroenterology
(Gastroenterology)
Vol. 108
Issue 5
Pg. 1487-95
(May 1995)
ISSN: 0016-5085 [Print] United States |
PMID | 7537235
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Dexamethasone
- Nitric Oxide Synthase
- Amino Acid Oxidoreductases
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Topics |
- Amino Acid Oxidoreductases
(antagonists & inhibitors, biosynthesis, physiology)
- Analysis of Variance
- Animals
- Blood Circulation
(drug effects)
- Dexamethasone
(pharmacology)
- Enzyme Induction
- Hemodynamics
(drug effects)
- Hypertension, Portal
(enzymology, physiopathology)
- Liver Cirrhosis, Experimental
(enzymology, physiopathology)
- Male
- Nitric Oxide Synthase
- Portal Pressure
(drug effects)
- Portal Vein
(physiopathology)
- Rats
- Rats, Sprague-Dawley
- Regional Blood Flow
(drug effects)
- Splanchnic Circulation
(drug effects)
- Stomach
(blood supply)
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