[Functional characterization of luminal enterocyte membranes of the small intestine mucosa using isolated brush border membranes].
Atrophy of the small intestinal mucosa is functionally characterized by a reduction in non-electrolyte transport in vivo. In order to elucidate the cellular defect being responsible for this malabsorption, we have studied the Na+-dependent D-glucose accumulation as well as the activities of aminopeptidase M and maltase in brush border membrane vesicles prepared from jejunal self-emptying blind loops and corresponding intestinal segments of sham-operated control rats. Membrane vesicles from atrophic mucosa did not show any differences in D-glucose uptake or in enzyme activities when compared with those derived from normal intestine. Thus it is unlikely that the impaired non-electrolyte absorption in the atrophic mucosa in vivo is due to a defect in cellular transport processes. It is more probable that the functional impairment is the result of the diminished absorptive surface in this pathophysiological condition.
D000626:Aminopeptidases / Q000378:metabolism; D000818:Animals; D001284:Atrophy; D001786:Blood Glucose / Q000378:metabolism; D018826:CD13 Antigens; D002462:Cell Membrane / Q000201:enzymology*; D005260:Female; D007408:Intestinal Absorption; D007413:Intestinal Mucosa / Q000201:enzymology*; D007583:Jejunum / Q000201:enzymology; D008286:Malabsorption Syndromes / Q000201:enzymology; D008871:Microvilli / Q000201:enzymology*; D051381:Rats; D011919:Rats, Inbred Strains; D000520:alpha-Glucosidases / Q000378:metabolism
D001786:Blood Glucose; D000520:alpha-Glucosidases; D000626:Aminopeptidases; D018826:CD13 Antigens
Funktionelle Charakterisierung luminaler Enterozytenmembranen atrophischer Dünndarmschleimhaut mittels isolierter Bürstensaum-Membranen.