Total parenteral nutrition decreases luminal mucous gel and increases permeability of small intestine

JPEN J Parenter Enteral Nutr. Jul-Aug 1994;18(4):346-50. doi: 10.1177/014860719401800412.


The distribution of fluorescein isothiocyanate dextran 70,000 (FITC-dextran) and mucous gel across the lumen of small intestine was observed as an investigation into the role of mucous gel on permeability in total parenteral nutrition (TPN). Thirty-two rats were randomly divided into two groups fed with either TPN or oral rat food. On day 4 or 7, FITC-dextran (750 mg/kg body weight) was given through the gastroduodenal tube. After 1 hour, blood samples were taken by aortic puncture to analyze plasma FITC-dextran by fluorescence spectrometry. Samples of small intestine with luminal contents were frozen and sectioned in a cryostat for fluorescence microscopy; the same sections were placed in a 0.2% celloidin solution for 3 minutes to preserve mucous gel and stained by periodic acid-Schiff reaction for light microscopy. The plasma level of FITC-dextran after 1 hour of this marker injection showed a significant increase (p < .01) in the TPN group compared with the rat food group on days 4 and 7. Morphologic findings on days 4 and 7 were similar in both the jejunum and ileum: The mucous gel filled the spaces between villi and FITC-dextran centered in the lumen in the rat food group, whereas the mucous gel decreased and FITC-dextran filled the spaces between villi in the TPN group. FITC-dextran and mucous gel showed complementary distributions in both groups. These data suggest that TPN decreases luminal mucous gel and increases permeability of small intestine in rats.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dextrans
  • Fluorescein-5-isothiocyanate / analogs & derivatives
  • Ileum / anatomy & histology
  • Intestinal Mucosa / metabolism*
  • Intestine, Small / anatomy & histology
  • Intestine, Small / metabolism*
  • Jejunum / anatomy & histology
  • Male
  • Microscopy, Fluorescence
  • Mucus / physiology*
  • Parenteral Nutrition, Total / adverse effects*
  • Permeability
  • Rats
  • Rats, Sprague-Dawley
  • Spectrometry, Fluorescence


  • Dextrans
  • fluorescein isothiocyanate dextran
  • Fluorescein-5-isothiocyanate