Small intestinal sugar and amino acid transport in semistarvation.
The effect of semistarvation on small intestinal transport of D-glucose, L-valine, and NaCl was studied in an in vitro system of isolated rat brush border membrane vesicles. Whereas semistarvation enhanced the transport rate for L-valine by 19-29%, there was no change in D-glucose transport. When energy in the form of a NaSCN gradient was supplied to the membrane vesicles prepared from semistarved animals, L-valine was concentrated to a greater extent than those from well-fed animals. Strain differences were observed in the manner semistarvation affected NaCl transport across the brush border membrane. Semistarvation increased the NaCl transport rate by a factor of 3.5 in one rat strain and not at all in another. These results provide a partial explanation for the cellular basis of elevated neutral amino acid absorption by the small intestine in semistarvation.
D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D050260:Carbohydrate Metabolism; D005947:Glucose / Q000378:metabolism; D066298:In Vitro Techniques; D007421:Intestine, Small / Q000378:metabolism*; D008297:Male; D008871:Microvilli / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012965:Sodium Chloride / Q000378:metabolism; D013217:Starvation / Q000378:metabolism*; D014633:Valine / Q000378:metabolism
D000596:Amino Acids; D012965:Sodium Chloride; D014633:Valine; D005947:Glucose