Hellier M D, Holdsworth C D, McColl I, Perrett D
Gut. 1972 Dec;13(12):965-9. doi: 10.1136/gut.13.12.965.
A quantitative perfusion method has been used to study intestinal absorption of two dipeptides-glycyl-glycine and glycyl-l-alanine-in normal subjects. In each case, the constituent amino acids were absorbed faster when presented as dipeptides than as free amino acids, suggesting intact dipeptide transport. During absorption constituent amino acids were measured within the lumen and it is suggested that these represent amino acids which have diffused back to the lumen after absorption as dipeptide. Portal blood analyses during absorption of a third dipeptide, glycyl-l-lysine, have shown that this dipeptide, known to be transported intact from the intestinal lumen, is hydrolysed to its constitutent amino acids before it reaches portal venous blood.
一种定量灌注方法已被用于研究正常受试者对两种二肽(甘氨酰甘氨酸和甘氨酰-L-丙氨酸)的肠道吸收情况。在每种情况下,组成二肽的氨基酸以二肽形式存在时比以游离氨基酸形式存在时吸收得更快,这表明存在完整的二肽转运。在吸收过程中,对肠腔内的组成氨基酸进行了测量,结果表明这些氨基酸代表了吸收后以二肽形式扩散回肠腔的氨基酸。在吸收第三种二肽甘氨酰-L-赖氨酸的过程中,对门静脉血的分析表明,这种已知从肠腔完整转运的二肽在到达门静脉血之前就被水解为其组成氨基酸。