[Circadian rhythmicity of the enzyme activity of different portions of the small intestine].

The circadian rhythms of maltase, alkaline phosphatase and dipeptide hydrolase were assessed in duodenum, proximal, medial and distal parts of the rat small intestine. Functional activities were assessed every 4 hrs for 24 hrs. Patterns of all enzymatic activities were different in different parts. The mucosal protein content in each segment of intestine was constant throughout the 24-hour period.