Potter G D, Schmidt K L, Lester R, Schultz S G
Am J Physiol. 1982 Jun;242(6):G642-9. doi: 10.1152/ajpgi.1982.242.6.G642.
In vitro intraluminal perfusion of the fetal rat ileum at 19 and 20 days of gestation was employed to measure the rate of glucose absorption and the unidirectional fluxes of 3-O-methylglucose (3-O-MG). Fetal ileum was mounted on pipettes within an oxygenated bath and perfused with a solution containing glucose or 3-O-MG and polyethylene glycol with average molecular weight of 4,000 (PEG) as a marker substance. We verified that the PEG was not transported and did not diffuse across the fetal ileum. Scanning and electron microscopy before and after perfusion demonstrated preservation of mucosal anatomy. The rate of glucose absorption was 200 +/- 17 mumol.h-1.g-1 at 19 days and increased significantly to 378 +/- 12 mumol.h-1.g-1 at 20 days. The absence of sodium abolished this process. The flux of 3-O-MG from lumen to bath was 88 +/- 10 mumol.h-1.g-1 at 19 days and 160 +/- 16 mumol.h-1.g-1 at 20 days. Bath-to-lumen flux was -17 +/- 2 mumol.h-1.g-1 and did not vary with age. Active, rapidly developing transport of glucose and 3-O-MG is demonstrated by in vitro luminal perfusion of the fetal rat ileum at 19 days.
在妊娠第19天和第20天，对胎鼠回肠进行体外腔内灌注，以测量葡萄糖吸收速率和3 - O - 甲基葡萄糖（3 - O - MG）的单向通量。将胎鼠回肠安装在充氧浴中的移液管上，并用含有葡萄糖或3 - O - MG以及平均分子量为4000的聚乙二醇（PEG）作为标记物质的溶液进行灌注。我们证实PEG不会被转运，也不会扩散穿过胎鼠回肠。灌注前后的扫描电子显微镜检查显示黏膜解剖结构得以保留。19天时葡萄糖吸收速率为200±17μmol·h⁻¹·g⁻¹，20天时显著增加至378±12μmol·h⁻¹·g⁻¹。无钠则消除了这一过程。19天时3 - O - MG从肠腔到浴液的通量为88±10μmol·h⁻¹·g⁻¹，20天时为160±16μmol·h⁻¹·g⁻¹。从浴液到肠腔的通量为 - 17±2μmol·h⁻¹·g⁻¹，且不随年龄变化。妊娠19天的胎鼠回肠体外腔内灌注证明了葡萄糖和3 - O - MG存在活跃的、快速发育的转运。
