Effects of ornithine aspartate on plasma ammonia and plasma amino acids in patients with cirrhosis. A double-blind, randomized study using a four-fold crossover design.

Abstract

This paper documents dose-dependent effects of ornithine aspartate (OA) on postprandial hyperammonemia and plasma amino acids. Ten patients with cirrhosis were randomized to undergo 1 out of 4 infusion series. Each series consisted of four 8-h infusions (09:00 h-17:00 h), with placebo (NaCl), 5 g, 20 g or 40 g of OA being administered on separate days in varying sequences. This 4-fold crossover design was double-blind. On infusion days, patients received 2 oral protein loads (0.25 g/kg at 09:00 h and 0.5 g/kg at 13:00 h). Venous blood samples were drawn every 2 h and the 24-h urine was collected. In addition to measuring plasma ammonia and amino acids, the urea production rate, serum glucose and serum insulin were analyzed. A significant postprandial rise in the ammonia concentration was noted during the infusions of placebo and 5 g of OA but did not occur with the dosages of 20 g (after the second protein load) and 40 g (after both protein loads). Furthermore, the latter dose, compared with placebo, significantly reduced plasma ammonia after the minor protein load. Urea production rate increased when 20 g or 40 g of OA was administered. Of the amino acids involved in the metabolic pathways of ornithine and/or aspartate, glutamate showed a rise in its plasma level following infusion of 40 g of OA, whereas glutamine did not. Concentrations of methionine, phenylalanine, tyrosine, threonine, serine and glycine declined progressively with increasing doses of OA (5-40 g). The highest dose of the drug caused hyperglycemia and hyperinsulinemia.(ABSTRACT TRUNCATED AT 250 WORDS)

• Authors: U Staedt, H Leweling, R Gladisch, C Kortsik, E Hagmüller, E Holm
• Journal: Journal of hepatology (J Hepatol) Vol. 19 Issue 3 Pg. 424-30 (Nov 1993) ISSN: 0168-8278 [Print] Netherlands
• PMID: 8151104 (Publication Type: Clinical Trial, Journal Article, Randomized Controlled Trial)

Chemical References

• Amino Acids
• Blood Glucose
• Dipeptides
• Insulin
• Ammonia
• Urea
• ornithylaspartate

Topics

• Adult
• Amino Acids (blood)
• Ammonia (blood)
• Blood Glucose (metabolism)
• Dipeptides (pharmacology)
• Double-Blind Method
• Female
• Humans
• Insulin (blood)
• Liver Cirrhosis (blood, drug therapy)
• Male
• Middle Aged
• Urea (blood)