膜蛋白流动的区域性： 小肠上皮细胞的吸收功能区域性 Na+/H+exchange mediates Na absorption in proximal small intestine Lumen Lamina propria Cell H Metabolism K N Na+ (1m0 Inhibited by increases ○at,Kt.ATs in cell calcium and cyclic nucleotides 膜蛋白流动的区域性： 小肠上皮细胞的吸收功能区域性