Regulation of the Na+-dependent high affinity glutamate/aspartate transporter in cultured Bergmann glia by phorbol esters.
The effects of phorbol 12-tetradecanoyl-13-acetate (TPA) and dibutyryl cAMP on the glutamate transport present in chick Bergmann glial cell (BGC) cultures were examined. TPA produced a significant decrease in [3H]-D-aspartate uptake, while dibutyryl cAMP treatment elicited a slight reduction in the transport. This effect was dose and time dependent and sensitive to staurosporine, a Ca2+/diacylglycerol-dependent protein kinase C (PKC) inhibitor. Long-term exposure of the culture to TPA results in a dramatic fall of the transporter activity and a decrease in the amount of the transporter protein. These findings suggest that PKC is involved in transport modulation and possibly in the regulation of the transporter gene expression.
González
M I
MI
Departamento de Genética y Biología Molecular, CINVESTAV-IPN, México D.F., México.
Ortega
A
A
D018528:ATP-Binding Cassette Transporters / Q000378:metabolism*; D027322:Amino Acid Transport System X-AG; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D003994:Bucladesine / Q000494:pharmacology*; D002478:Cells, Cultured; D002642:Chick Embryo; D017868:Cyclic AMP-Dependent Protein Kinases / Q000187:drug effects; D004789:Enzyme Activation; D009457:Neuroglia / Q000187:drug effects* / Q000378:metabolism; D018377:Neurotransmitter Agents / Q000378:metabolism; D011493:Protein Kinase C / Q000187:drug effects; D012964:Sodium / Q000494:pharmacology*; D013569:Synapses / Q000187:drug effects; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014316:Tritium
D018528:ATP-Binding Cassette Transporters; D027322:Amino Acid Transport System X-AG; D018377:Neurotransmitter Agents; D014316:Tritium; D003994:Bucladesine; D012964:Sodium; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate