Moe A J, Pocius P A, Polan C E
J Nutr. 1985 Sep;115(9):1173-9. doi: 10.1093/jn/115.9.1173.
Intestinal brush border membrane vesicles were prepared from 21-wk-old Holstein bulls. The method of preparation included magnesium precipitation, differential centrifugation and sucrose density gradient centrifugation. Purification of brush border membranes was indicated by sevenfold enrichment of alkaline phosphatase activity. Uptake of D-[U-14C]glucose was sodium-stimulated and exhibited characteristic "overshoot" phenomenon. Sodium-dependent and sodium-independent D-glucose uptake was into an osmotically active space. Phloridzin (100 mM) completely inhibited sodium-dependent, but did not affect sodium-independent transport. Sodium-dependent D-glucose transport was inhibited more by D-glucose than by D-galactose, which inhibited more than D-xylose did. The sodium-dependent D-glucose transport was not inhibited by D-fructose, D-ribose or D-arabinose. Sodium-independent D-glucose transport was unaffected by the sugars tested. Glucose transport in bovine intestinal brush border is similar to that in monogastric species and is composed of two pathways: a sodium-dependent inhibitable system and a diffusional system.
从21周龄的荷斯坦公牛制备肠刷状缘膜囊泡。制备方法包括镁沉淀、差速离心和蔗糖密度梯度离心。碱性磷酸酶活性富集七倍表明刷状缘膜得到了纯化。D-[U-14C]葡萄糖的摄取受钠刺激，并表现出典型的“过冲”现象。钠依赖性和非钠依赖性D-葡萄糖摄取进入渗透活性空间。根皮苷（100 mM）完全抑制钠依赖性转运，但不影响非钠依赖性转运。D-葡萄糖比D-半乳糖更能抑制钠依赖性D-葡萄糖转运，而D-半乳糖比D-木糖更能抑制该转运。钠依赖性D-葡萄糖转运不受D-果糖、D-核糖或D-阿拉伯糖的抑制。非钠依赖性D-葡萄糖转运不受所测试糖类的影响。牛肠刷状缘中的葡萄糖转运与单胃动物相似，由两条途径组成：钠依赖性可抑制系统和扩散系统。
