Ophthalmology Poster Session

Non-vectorial transporter

Dr. Ayoub: Thanx for your answer but you should think of the Na-dependence. You can also Li-load the cells to get them Na-free to see if the loss of glucose depends on intracellular Na!
Cheers
akg

On Thu Dec 10, george ayoub wrote
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>On Sun Dec 6, Grover wrote
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>>Dr. Ayoub: Fascinating results. Hope you are having fun at the meeting. Have you tried to see if the release of glucose is Na+-dependent by carrying out the experiments using Na+-depleted (one can use N-methylglucamine) glial cells to see if they release glutamate?
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>Dr. Grover: Thank you for the comments. We have not yet directly tested the Na-dependence in our system, though this mechanism has been previously explored by Dr. Attwell and his colleagues using patch clamp techniques on isolated Muller cells. They find glutamate transport to be via a Na-dependent mechanism, with the Na electrochemical gradient driving the movement of glutamate across the membrane of the glial cels. Thus, these cells typically accumulate glutamate, but when the energetics of the transport are modified (via depolarization of the cell, for example), the glial cells secrete glutamate.

Thu Dec 10