Mesenteric Venous Stenosis Reduces Hyperammonemia in the Portacaval Shunted Rat
Part of the
Experimental Biology and Medicine
book series (EBAM, volume 22)
Hyperammonemia is a constant finding following portacaval anastomosis (PCA), and has been incriminated in the genesis of post-shunt encephalopathy (PSE) in the human. We developed a model for mesenteric venous hypertension in the rat by modification of a commonly-used technique for studying extrahepatic portal hypertension. We then examined serum ammonia levels in rats undergoing sham operation, mesenteric vein stenosis (MVS) alone, PCA alone, and MVS plus PCA.
MVS animals had significant (p < 0.05) elevation in mesenteric venous pressures two to three weeks after operation. Serum ammonia levels were normal in rats undergoing sham operation and MVS, and were significantly elevated (p < 0.001) in rats with PCA. However, combination of MVS and PCA resulted in a significant (p < 0.01) reduction in serum ammonia levels.
These data suggest that ammonia absorption from the intestine is a function of splanchnic venous pressure. This finding may be relevant to the management of the neuropsychiatric deterioration seen following PCA in the human.
KeywordsHepatic Encephalopathy Portacaval Shunt Portal Vein Stenosis Serum Ammonia Level Portacaval Anastomosis
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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