Correlation between Morphological Alterations and Enzyme Activities in the Mucosa of the Small Intestine

Abstract

Berg, N. O., Dahlqvist, A., Lindberg, T. & Nordén, Å. Correlation between morphological alterations and enzyme activities in the mucosa of the small intestine. Scand. J. Gastroent. 1973, 8, 703-712.

Material for the present study represented 233 small intestinal biopsies taken from 178 adult patients with various gastrointestinal complaints. Parallel analyses were made of morphology (mucosal surface by dissection microscope inspection, mucosal index, distance from top of villi to bottom of crypts over depth of the crypts, and cellular changes), of intestinal dipeptidases (substrates: ala-glu, ala-pro, gly-leu, gly-val, glu-pro, glu-val, val-glu, and val-pro), and of intestinal disaccharidases (maltase, sucrase, isomaltase, lactase, and trehalase). A statistical study of the correlation between these parameters showed: 1) All enzyme activities were significantly correlated to the morphological findings. The ala-pro dipeptidase activity was the one that was most strongly correlated to the morphology score, followed by lactase. 2) In severely pathological intestinal mucosa the disaccharidase activities were much more depressed than the dipeptidase activities. 3) Sucrase and isomaltase were strongly correlated to each other, as gly-leu and gly-val dipeptidase activities, and ala-pro and glu-pro dipeptidase activities. There was a significant increase of the disaccharidase activities from the proximal part (duodenum) to the middle and distal parts of the gut. The increase for the dipeptidase activities was less obvious and only significant for peptidyl-proline dipeptidase activity.

Key-words::

• Intestinal biopsy
• intestinal dipeptidase
• intestinal disaccharidases
• intestinal mucosa