Effect of intraduodenal and intravenous amino acids on proximal gastric motor function in man

The present study was performed to investigate the effect of amino acids du ring the intestinal and postabsorptive phase of digestion on proximal gastr ic motor function measured with an electronic barostat. Eight healthy volun teers participated in three experiments performed during continuous infusio n of: (1) intravenous and intraduodenal saline, (2) intraduodenal amino aci ds, and (3) intravenous amino acids. Both intraduodenal and intravenous ami no acids induced gastric relaxation and increased gastric compliance. Only during intraduodenal amino acids did plasma CCK levels increase significant ly. Correlation between intragastric volume measurements (with pressure set at MDP + 2 mm Hg) and plasma CCK levels was 0.90 (P < 0.001) during the ea rly intestinal phase. Relaxation of the proximal stomach is related to plas ma CCK in the early intestinal phase, whereas in the postabsorptive phase o f amino acids other mechanisms play a role in proximal gastric relaxation.