THE EFFECTS OF PROTEIN-INTAKE ON DIFFERENCES BETWEEN NAA AND EAA IN GUT CONTENT OF RAT JEJUNUM AND ILEUM AFTER SHORT AND LONG-TERM DIETARY-TREATMENT

Young Wistar rats were fed isoenergetic diets with 0.5, 15 and 50% cas ein ad libitum for 7 and 21 days, respectively. Differences between mo lar proportions of nonessential (NAA) and essential amino acids (EAA) in jejunal and ileal gut contents under postprandial conditions, were measured. The results showed that the differences between NAA and EAA were more expressed in the ileum than in the jejunum especially after the longer treatment due to the higher values of NAA than EAA regardle ss of the protein intake. At the same time, there was a tendecy for th e NAA/EAA differences to decrease after the longer treatment, especial ly in the jejunum. These frindings support the concept of intraluminal homeostasis of amino acids in the jejunum after different protein int akes for longer periods as well as a possible greater accumulation of NAA than EAA in ileal gut content.