[Renal origin of hyperammonemia induced by an high-protein diet in normal rats or those with portal stricture].
Hyperammonemia is observed in high protein diet fed cirrhotic and is thought to be related to an increased intestinal ammoniagenesis. We studied this problem in control rats and rats with a portal stricture and portal systemic shunts given a high protein or a standard diet. In those animals the systemic, portal and renal venous ammonemia and glutaminemia were measured. In rats with portal stricture on a high protein diet, the increase in systemic ammonemia did not significantly differ from that found in animals on a standard diet. In contrast, the control group exhibited a higher level (P less than 0.001) of systemic ammonemia after a high protein (102 +/- 7 SEM mumol/l) than after standard diet (36 +/- 1). This hyperammonemia appeared to be of renal origin since there was a significantly higher ammonia difference between renal venous and arterial blood with the high protein than with standard feeding, both in rats with a portal stricture (+ 229 +/- 32 vs. + 24 +/- 8 mumol/l; P less than 0.001). and in control rats (+ 196 +/- 23 vs. + 2 +/- 11; P less than 0.001). This increased renal ammonia release into the circulation induced by the high protein diet was associated with a high renal uptake of circulating glutamine. Moreover, a decreased ammonia passage from the digestive tract into the portal vein and disappearance of intestinal uptake of circulating glutamine was also observed with the high protein feeding.(ABSTRACT TRUNCATED AT 250 WORDS)
D000641:Ammonia / Q000097:blood*; D000818:Animals; D003250:Constriction; D004044:Dietary Proteins / Q000494:pharmacology*; D007668:Kidney / Q000503:physiopathology*; D008297:Male; D011169:Portal Vein / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains
D004044:Dietary Proteins; D000641:Ammonia
Origine rénale de l'hyperammoniémie provoquée par un régime hyperprotidique chez le rat normal ou porteur d'une stricture portale.