Effect of Acute Exposure to Ammonia on Glutamate Transport in Glial Cells Isolated From the Salamander Retina -- Mort et al. 86 (2): 836 -- Journal of Neurophysiology

Effect of Acute Exposure to Ammonia on Glutamate Transport in Glial Cells Isolated From the Salamander Retina -- Mort et al. 86 (2): 836 -- Journal of Neurophysiology: "For hepatic encephalopathy, the decrease in glutamate uptake at late times, caused by reduced transporter expression, is more important than the initial increase of uptake. Transporter expression can be regulated by cAMP and several growth factors (Zelenaia et al. 2000). Conceivably modulation of the latter pathways by NH or altered pH might lead to downregulation. Alternatively, it is possible that cells have a mechanism for sensing the amount of intracellular glutamate and regulating transporter expression accordingly. In this case, the increased uptake at early times that we have characterized, which presumably leads, initially, to a rise of intracellular glutamate concentration, could be a trigger for a long-lasting downregulation of transporter expression."