Knudsen G M, Jakobsen J, Barry D I, Compton A M, Tomlinson D R
Department of Neurology, Rigshospitalet, Copenhagen, Denmark.
Neuroscience. 1989;29(3):773-7. doi: 10.1016/0306-4522(89)90148-6.
The effect of a dietary supplement of an aldose reductase inhibitor (ponalrestat) or of myo-inositol on sodium transport into the rat brain and on concentrations of saccharide and polyols in cortical brain tissue and sciatic nerve was investigated in control rats and in streptozotocin-diabetic rats after a diabetes duration of 2 weeks. In untreated diabetes, the neocortical blood-brain barrier permeability for sodium decreased by 28% (3.4 +/- 0.4 vs 4.7 +/- 1.6 x 10(-5) ml/s g, mean +/- SD) as compared to controls. Levels of glucose, sorbitol and fructose increased in brain as well as in nerve tissues, whereas myo-inositol depletion was not demonstrable. Ponalrestat treatment of diabetic animals had no effect upon the decreased neocortical blood-brain barrier permeability to sodium (3.5 +/- 0.9 vs 4.7 +/- 1.1 x 10(-5) ml/s g) despite normalization of brain and nerve content of sorbitol and fructose. Myo-inositol supplementation of diabetic rats normalized sodium passage into the brain (4.2 +/- 1.1 vs 4.4 +/- 0.5 x 10(-5) ml/s g). Brain concentrations of monosaccharides and polyols were normalized as compared to the myo-inositol treated control group and nerve concentrations of glucose, sorbitol, and fructose were significantly increased. Myo-inositol treatment leads to a normalization of blood-brain barrier permeability; it is suggested that myo-inositol exerts a restituting effect upon Na+/K+-ATPase activity of the cerebral endothelial cells.
在对照大鼠和糖尿病病程为2周的链脲佐菌素诱导的糖尿病大鼠中，研究了膳食补充醛糖还原酶抑制剂（泊那司他）或肌醇对钠转运入大鼠脑内以及对大脑皮质组织和坐骨神经中糖类和多元醇浓度的影响。在未经治疗的糖尿病大鼠中，与对照组相比，新皮质血脑屏障对钠的通透性降低了28%（3.4±0.4对4.7±1.6×10⁻⁵ ml/s g，平均值±标准差）。脑和神经组织中的葡萄糖、山梨醇和果糖水平升高，而肌醇耗竭未得到证实。对糖尿病动物进行泊那司他治疗，尽管脑和神经中山梨醇和果糖含量恢复正常，但对新皮质血脑屏障对钠通透性降低并无影响（3.5±0.9对4.7±1.1×10⁻⁵ ml/s g）。给糖尿病大鼠补充肌醇可使钠进入脑内的过程恢复正常（4.2±1.1对4.4±0.5×10⁻⁵ ml/s g）。与肌醇治疗的对照组相比，脑中的单糖和多元醇浓度恢复正常，神经中葡萄糖、山梨醇和果糖的浓度显著升高。肌醇治疗可使血脑屏障通透性恢复正常；提示肌醇对脑内皮细胞的Na⁺/K⁺-ATP酶活性具有恢复作用。
