Acidosis modifies metabolic functions but does not affect vascular resistances in perfused rat livers.
BACKGROUND
Few data exist concerning the consequences of acidosis on intrahepatic vascular resistances and hepatic functions.


METHODS
The consequences of pH and PCO2 changes on the intrahepatic vascular reactivity to norepinephrine (NE, 10(-9) to 3 x 10(-5) M) have been investigated in isolated rat livers perfused with solutions bubbled with 5, 10, or 15% CO2 and in solutions in which pH was decreased by replacing HCO3- with NaCl while maintaining a normal PCO2. Hepatic O2 consumption (VO2) and urea release were also measured during these experiments.


RESULTS
The NE-induced increase of portal pressure did not change during hypercarbic and normocarbic acidosis. In contrast, the NE-induced increase of urea release was higher when the solution of perfusion was bubbled with 10 and 15% CO2, while during normocarbic acidosis the NE-induced increase of urea release did not change with pH. In the absence of NE, acidosis decreased hepatic VO2 and urea release but portal pressure was not modified by changing % CO2 or pH in the Krebs-Henseleit-bicarbonate solution.


CONCLUSIONS
This study clearly shows that, in the liver, the consequences of acidosis are far more important on the metabolism (VO2 and urea release) than on the intrahepatic vascular resistance.
Pastor
C M
CM
Division d'Hépatologie et de Gastroentérologie, Hĵpital Cantonal Universitaire de Genève, Switzerland. catherine.pastor@medecine.unige.ch
Hadengue
A
A
D000138:Acidosis / Q000378:metabolism / Q000503:physiopathology*; D000818:Animals; D002245:Carbon Dioxide / Q000378:metabolism; D008102:Liver Circulation / Q000187:drug effects; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology; D010313:Partial Pressure; D010477:Perfusion; D011168:Portal System / Q000503:physiopathology; D011312:Pressure; D051381:Rats; D017207:Rats, Sprague-Dawley; D014508:Urea / Q000378:metabolism; D014655:Vascular Resistance / Q000187:drug effects; D014662:Vasoconstrictor Agents / Q000494:pharmacology
D014662:Vasoconstrictor Agents; D002245:Carbon Dioxide; D014508:Urea; D009638:Norepinephrine