Choline uptake by isolated enterocytes of guinea pig.
Isolated intestinal epithelial cells of guinea pig were employed to study choline transport. Uptake by cells from the whole length of the small intestine was saturable with an apparent Km value of 119 microM and Vmax of 208 pmol/(mg protein X minute). The compound was taken up by ileal cells about three times faster than by jejunal cells. Antimycin A reduced the rate of uptake more than 50%. Inhibition of the (Na+ + K+)-ATPase by ouabain or replacement of Na+ in the medium by K+ decreased the rate of uptake. The results indicate that choline is absorbed in the jejunum and ileum of guinea pig mainly by an Na+-dependent carrier mechanism.
D000818:Animals; D000968:Antimycin A / Q000494:pharmacology; D001693:Biological Transport, Active; D002794:Choline / Q000378:metabolism*; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects / Q000378:metabolism; D066298:In Vitro Techniques; D007421:Intestine, Small / Q000187:drug effects / Q000378:metabolism*; D007583:Jejunum / Q000187:drug effects / Q000378:metabolism; D008297:Male; D010042:Ouabain; D011188:Potassium / Q000494:pharmacology; D012964:Sodium / Q000494:pharmacology; D014316:Tritium
D014316:Tritium; D010042:Ouabain; D000968:Antimycin A; D012964:Sodium; D002794:Choline; D011188:Potassium