Barber A, Jordana R, Ponz F
Rev Esp Fisiol. 1979 Jun;35(2):243-8.
Everted intestinal rings of the snail Cryptomphalus hortensis accumulate labelled sugars against a concentration gradient. The active transport of D-galactose (KT = 3.6 mM) is competitively inhibited by D-glucose (Ki = 8.2 mM) and by 3-0-methylglucose (Ki = 24 mM), but it is not affected by L-arabinose, D-fructose, L-arabinose and D-mannitol penetrate into the tissue at the same rate, they do not develop accumulation gradient, and all of them follow the kinetics of a diffusion process. D-glucose, on the contrary, like galactose, penetrates much more quickly and accumulates against a gradient.
园圃隐带螺的外翻肠环能逆浓度梯度积累标记糖。D-半乳糖（转运常数KT = 3.6 mM）的主动转运受到D-葡萄糖（抑制常数Ki = 8.2 mM）和3-O-甲基葡萄糖（抑制常数Ki = 24 mM）的竞争性抑制，但不受L-阿拉伯糖、D-果糖、L-阿拉伯糖和D-甘露醇的影响，它们以相同速率进入组织，不会形成积累梯度，且均遵循扩散过程的动力学。相反，D-葡萄糖与半乳糖一样，穿透速度快得多且能逆梯度积累。
