Effect of parenteral l-amino acids on gastric secretion and serum gastrin in normal dogs and dogs with portacaval transposition

: The effect of intravenous infusion of L-amino acids (FreAmine II) on gastric secretion and on circulating levels of gastrin was studied in five gastric fistula dogs and three dogs with portacaval transposition. Significant increases in gastric acid secretion were found after infusions which delivered 2.0, 4.0, and 8.0 gm/hr of L-amino acids in five gastric fistula dogs. After portacaval transposition, administration of amino acid solutions via the hindleg (through the liver) resulted in a great fall in the acid secretory response. Gastrin levels were significantly elevated after 8.0 gm/hr of amino acids. After 2.0 and 4.0 gm/hr, there was a slight but insignificant increase in serum gastrin levels. Gastrin levels were unchanged after infusion of 8.0 gm/hr of L-amino acids through the liver. We conclude that L-amino acids given intravenously stimulate gastric acid secretion in a dose-dependent manner by a mechanism which does not involve gastrin. At the highest dosage of amino acids, some gastrin was released which might have stimulated acid output further.