Adenosine and hemodynamic alterations in cirrhotic rats.
This study evaluated the hypothesis that adenosine may participate in the hemodynamic alterations observed in conscious unrestrained cirrhotic rats. In sham-operated rats, adenosine (20 micrograms.100 g body wt-1.min-1 iv) induced hyperdynamic circulation and significantly increased portal pressure, mimicking the hemodynamic changes observed in cirrhosis. Although adenosine significantly increased hyperdynamic circulation and portal pressure in cirrhotic rats, these changes were significantly less marked than in sham-operated rats. 8-Phenyltheophylline (20 micrograms.100 g body wt-1.min-1 iv), a specific and potent adenosine antagonist, significantly decreased portal tributary blood flow in sham-operated rats (-18.0 +/- 5.6%) but did not have a significant effect in cirrhotic rats. The limited effect of 8-phenyltheophylline was not due to an insufficient dose, since the dose administered antagonized the hemodynamic effect of exogenous adenosine up to 40 micrograms.100 g body wt-1.min-1. We conclude that in certain circumstances, although adenosine may aggravate the hyperdynamic circulation, in normal conditions, the hemodynamic alterations observed in cirrhotic rats are not mediated by adenosine.
Champigneulle
B
B
Laboratoire d'Hémodynamique Splanchnique, Institut National de la Santé et de la Recherche Médicale Unité 24, Clichy, France.
Braillon
A
A
Kleber
G
G
Gaudin
C
C
Cailmail
S
S
Lebrec
D
D
D000241:Adenosine / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D008102:Liver Circulation / Q000187:drug effects; D008105:Liver Cirrhosis, Biliary / Q000503:physiopathology*; D008106:Liver Cirrhosis, Experimental / Q000503:physiopathology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values; D012079:Renal Circulation / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects
D000241:Adenosine