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