Effect of osmolality and myo-inositol deprivation on the transport properties of myo-inositol in primary astrocyte cultures.

摘要: myo-Inositol uptake measured in primary astrocyte cultures was saturable the presence of Na+ with a Km 13–18 μM and Vmax 9.4 nmoles/mg protein/hour myo-inositol-fed cells, indicating high affinity transport system. In myo-inositol-deprived about 53 13.2 protein/hour. Decreasing osmolality decreased to 1.9 whereas increasing increased 5-fold, while Kms were essentially unchanged myo-inositol fed cells. cells deprived myo-inositol, hypotonic medium hypertonic almost 10-fold, but more than doubling regardless osmolality. Glucose (25 mM) inhibited 51% other hexoses used much less. Our findings indicate that astrocytes occurs through an efficient carrier-mediated Na+-dependent co-transport system is different from glucose its kinetic properties are affected by availability osmotic stress.