These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: A high yield preparation of brush border membrane vesicles from organ-cultured embryonic chick jejunum: demonstration of insulin sensitivity of Na(+)-dependent D-glucose transport.
    Author: Debiec H, Cross HS, Peterlik M.
    Journal: J Nutr; 1991 Jan; 121(1):105-13. PubMed ID: 1992047.
    Abstract:
    Although embryonic chick small intestinal segments provide a very limited amount of tissue for preparation of enterocyte brush border membrane vesicles (BBMV), we were able to develop a procedure for isolation of BBMV from cultured 20-d-old embryonic chick jejunum in high yield by modifying a divalent cation precipitation method. Total yield of the brush border marker enzyme alkaline phosphatase in the vesicle fraction as compared to the crude homogenate was approximately 40%, and the specific activity of the enzyme was increased 25-fold on the average. The brush border membrane vesicle fraction was only contaminated with other cellular organelles (basolateral membranes, mitochondria, lysosomes or endoplasmic reticulum) to a minor extent. Functional integrity of the brush border vesicles was indicated by Na+ gradient-driven electrogenic D-glucose transport leading to concentrative transfer (overshoot) of the sugar into an osmotically active intravesicular space. When jejuna were cultured for 48 h in the presence of 10(-6) mol/L insulin, the initial rate of Na(+)-dependent D-glucose uptake by brush border membrane vesicles as well as Na(+)-dependent [3H]phlorizin binding to brush border membranes was approximately twice as high as in vesicles from untreated controls. This strongly suggests that insulin could enhance intestinal absorption of D-glucose by increasing the intrinsic activity of the Na(+)-dependent D-glucose transport system at the luminal membrane of enterocytes.
    [Abstract] [Full Text] [Related] [New Search]