Effect of starvation on neutral amino acid transport in isolated small-intestinal cells from guinea pigs.

Abstract

The effects of starvation on neutral amino acid transport were examined in isolated enterocytes. Starvation stimulated L-alanine transport by the Na(+)-dependent system A and the Na(+)-independent system L without producing any changes in either the Na(+)-dependent systems ASC or the passive non-mediated uptake. Starvation produces a twofold increase in Vmax of system A without any change in Kt. Starvation produces an increase in Vmax of system L of 1.7 times without any change in Kt. Activation of systems A and L by starvation was reversible with subsequent refeeding. The effects of a series of amino acids on systems A and L were evaluated. A different inhibition pattern was found in starved animals as compared to controls. Starvation increases Na(+)-dependent L-alanine uptake and Na(+)-independent cycloleucine uptake by small-intestinal brush-border membrane vesicles. These results suggest that starvation stimulates amino acid transport across the apical plasma membrane of the enterocytes by inducing specific carrier units.

• Authors: R Muñíz, L Burguillo, J R del Castillo
• Journal: Pflugers Archiv : European journal of physiology (Pflugers Arch) Vol. 423 Issue 1-2 Pg. 59-66 (Apr 1993) ISSN: 0031-6768 [Print] Germany
• PMID: 8488093 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Amino Acids
• Cycloleucine
• beta-Alanine
• 2,2-dimethyl-beta-alanine
• Sodium
• Alanine

Topics

• Alanine (metabolism)
• Amino Acids (metabolism, pharmacology)
• Animals
• Biological Transport (drug effects)
• Cell Membrane (metabolism)
• Cycloleucine (metabolism)
• Guinea Pigs
• Ileum (metabolism)
• Intestinal Absorption (drug effects)
• Intestine, Small (drug effects, metabolism)
• Jejunum (metabolism)
• Male
• Sodium (pharmacology)
• Starvation (metabolism)
• beta-Alanine (analogs & derivatives, metabolism)