McArthur K E, Isenberg J I, Hogan D L, Dreier S J
J Clin Invest. 1983 May;71(5):1254-62. doi: 10.1172/jci110875.
To determine whether intravenous infusion of individual amino acids stimulated gastric acid secretion in man, graded doses of phenylalanine, tryptophan, glycine, alanine, histidine, and NaCl control were infused on separate days in nine healthy subjects. Intravenous infusion of phenylalanine and tryptophan significantly stimulated gastric acid secretion to 50 and 52%, respectively, of the acid secretory response to intragastric peptone. Intravenous alanine and histidine were without effect, whereas glycine produced a slight response. Serum gastrin concentrations did not significantly change during intravenous amino acid infusion, except in response to 0.1 M phenylalanine. However, the increase in serum gastrin occurred 2 h after acid secretion had significantly increased in response to the 0.025 M phenylalanine infusion. Plasma amino acid concentrations were measured during intravenous amino acid infusion and in response to a steak meal in five of the subjects. At a time when acid secretion was significantly increased during intravenous infusion of phenylalanine and tryptophan, plasma amino acids were similar to, or less than, that observed after the steak meal, suggesting that circulating levels of these three amino acids have a physiologic effect on gastric secretion in man. Intravenous infusion of a combination of graded doses of phenylalanine plus a continuous infusion of 0.01 M tryptophan shifted the dose-response curve to the left and resulted in a significantly greater response than to either amino acid alone. In five subjects with parietal cell vagotomy, intravenous phenylalanine and tryptophan stimulated acid secretion, whereas histidine was without effect, similar to normal subjects. These studies indicate that intravenous infusion of small amounts of phenylalanine (0.025 M, 3.1 mmol/h) and tryptophan (0.01 M, 1.25 mmol/h) stimulated gastric acid secretion at plasma concentrations similar to those observed after a steak meal, suggesting a physiologic role for circulating levels of these amino acids on gastric acid secretion. Because acid secretion increased at a time when serum gastrin was unchanged and since there was no correlation between changes in serum gastrin and acid secretion, the responses to phenylalanine and tryptophan are probably mediated by a nongastrin-related mechanism(s). Since both phenylalanine and tryptophan stimulated secretion in vagotomized subjects, the response is vagally independent. These observations suggest that circulating levels of these two amino acids have either a direct or indirect effect on or near the human parietal cell.
为了确定静脉输注单个氨基酸是否会刺激人体胃酸分泌，在9名健康受试者中，于不同日期分别输注不同剂量的苯丙氨酸、色氨酸、甘氨酸、丙氨酸、组氨酸以及氯化钠作为对照。静脉输注苯丙氨酸和色氨酸分别使胃酸分泌显著增加至胃内注入蛋白胨后酸分泌反应的50%和52%。静脉输注丙氨酸和组氨酸无作用，而甘氨酸产生轻微反应。静脉输注氨基酸期间，血清胃泌素浓度除对0.1M苯丙氨酸有反应外无显著变化。然而，在对0.025M苯丙氨酸输注产生显著酸分泌增加后2小时血清胃泌素才升高。在5名受试者中，于静脉输注氨基酸期间以及对牛排餐的反应过程中测量血浆氨基酸浓度。在静脉输注苯丙氨酸和色氨酸导致酸分泌显著增加时血浆氨基酸与牛排餐后观察到的相似或更低，这表明这三种氨基酸的循环水平对人体胃酸分泌具有生理作用。静脉输注不同剂量苯丙氨酸加持续输注0.01M色氨酸的组合使剂量 - 反应曲线左移，且产生的反应显著大于单独使用任何一种氨基酸。在5名壁细胞迷走神经切断术患者中，静脉输注苯丙氨酸和色氨酸刺激酸分泌，而组氨酸无作用，这与正常受试者相似。这些研究表明，静脉输注少量苯丙氨酸（0.025M，3.1mmol/h）和色氨酸（0.01M，1.25mmol/h）在血浆浓度与牛排餐后观察到的相似时刺激胃酸分泌，提示这些氨基酸的循环水平对胃酸分泌具有生理作用。由于在血清胃泌素未改变时酸分泌增加，且血清胃泌素变化与酸分泌之间无相关性，对苯丙氨酸和色氨酸的反应可能由非胃泌素相关机制介导。由于苯丙氨酸和色氨酸在迷走神经切断术患者中均刺激分泌，该反应不依赖迷走神经。这些观察结果表明，这两种氨基酸的循环水平对人壁细胞或其附近具有直接或间接作用。
