Regulation of the glutamate transporter by amino acid deprivation and associated effects on the level of EAAC1 mRNA in the renal epithelial cell line NBL-1
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چکیده
The glutamate transport system of the bovine renal epithelial cell line NBL-1 was studied. The Km for Na+-dependent glutamate transport was found to be 13.8 + 2.4 ,ltM (Vmax. 365 + 19.2 pmol/3 min per mg) and for Na+-dependent aspartate transport 4.5 + 1.1 ,uM (Vmax. 108 6.3 pmol/3 min per mg). The Km values are in close agreement with those expected for high-affinity Na+-dependent glutamate transport by System XAG-. Upon deprivation of amino acids, the Vma. for Na+/ aspartate co-transport rose to 203 + 6.0 pmol/3 min per mg
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Regulation of high-affinity glutamate transport by amino acid deprivation and hyperosmotic stress.
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