Said H M, Ghishan F K, Murrell J E
Diabetes Res. 1986 Sep;3(7):363-7.
The effect of chemically-induced acute diabetes mellitus on the intestinal transport of 5-methyltetrahydrofolate, the predominate dietary form of folate, was examined using an in vivo perfusion technique in unanesthetized restrained rats and the in vitro everted sac technique. Diabetes was induced by an intraperitoneal injection of 70 mg/kg of streptozotocin. Transport experiments were performed 4 days after the induction of diabetes and results were compared to appropriate controls. The amount of 5-methyltetrahydrofolate transported in vivo and in vitro was significantly higher in the diabetic group as compared to controls. The kinetic parameters of the in vitro transport of 5-methyltetrahydrofolate showed an increase in the Vmax value for the diabetic rats as compared to controls (1.52 and 0.80 nmol/g initial tissue wet wt/30 min, respectively) with no change in apparent Kt (1.62 and 1.80 microM, respectively). These observations suggest that the increase in the transport of 5-methyltetrahydrofolate observed in the diabetic rats is due to an increase in the activity and/or the number, but not the affinity, of the transport carriers involved. We conclude that chemically-induced acute diabetes mellitus is associated with an enhancement in folate absorption.
使用体内灌注技术，在未麻醉的束缚大鼠身上以及体外翻转肠囊技术，研究了化学诱导的急性糖尿病对肠道中5-甲基四氢叶酸（叶酸的主要膳食形式）转运的影响。通过腹腔注射70mg/kg链脲佐菌素诱导糖尿病。在糖尿病诱导4天后进行转运实验，并将结果与适当的对照组进行比较。与对照组相比，糖尿病组体内和体外转运的5-甲基四氢叶酸量显著更高。5-甲基四氢叶酸体外转运的动力学参数显示，糖尿病大鼠的Vmax值相较于对照组有所增加（分别为1.52和0.80nmol/g初始组织湿重/30分钟），而表观Kt无变化（分别为1.62和1.80μM）。这些观察结果表明，糖尿病大鼠中5-甲基四氢叶酸转运增加是由于所涉及转运载体的活性和/或数量增加，而非亲和力增加。我们得出结论，化学诱导的急性糖尿病与叶酸吸收增强有关。
