豚鼠离体肠上皮细胞对胆碱的摄取

Choline uptake by isolated enterocytes of guinea pig.

作者信息

Hegazy E, Schwenk M

出版信息

J Nutr. 1984 Dec;114(12):2217-20. doi: 10.1093/jn/114.12.2217.

DOI:10.1093/jn/114.12.2217

Abstract

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.

摘要

采用豚鼠分离的肠上皮细胞来研究胆碱转运。小肠全长细胞对胆碱的摄取具有饱和性，表观 Km 值为 119 μM，Vmax 为 208 pmol/(mg 蛋白×分钟)。回肠细胞对该化合物的摄取速度比空肠细胞快约三倍。抗霉素 A 使摄取速率降低超过 50%。哇巴因抑制(Na+ + K+)-ATP 酶或用 K+替代培养基中的 Na+会降低摄取速率。结果表明，胆碱在豚鼠空肠和回肠主要通过 Na+依赖的载体机制被吸收。