High-voltage-activated calcium channels in Mueller cells acutely isolated from tiger salamander retina

High-voltage-activated calcium channels in Mueller cells acutely isolated from tiger salamander retina

Mueller cells mediate retinal function by stabilizing the ionic environment and signal glial network activity via calcium waves. Using whole-cell patch clamp recording, we describe a high-voltage-activated, slowly inactivating Ca channel current in isolated salamander Mueller cells that has unusual...

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Veröffentlicht in:Glia 2005-01, Vol.49 (2), p.259-274
Hauptverfasser: Welch, Nicole C, Wood, Stephanie, Jollimore, Christine, Stevens, Kelly, Kelly, Melanie EM, Barnes, Steven
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Ambystoma tigrinum
Caudata
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container_title Glia
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creator Welch, Nicole C
Wood, Stephanie
Jollimore, Christine
Stevens, Kelly
Kelly, Melanie EM
Barnes, Steven
description Mueller cells mediate retinal function by stabilizing the ionic environment and signal glial network activity via calcium waves. Using whole-cell patch clamp recording, we describe a high-voltage-activated, slowly inactivating Ca channel current in isolated salamander Mueller cells that has unusual pharmacological properties. The Ca channel current has an activation midpoint of [sim]-8 mV and an inactivation midpoint of [sim]-26 mV in 10 mM Ba super(2+). The time constant for inactivation is [sim]380 ms at potentials positive to zero. The current is blocked by Cd super(2+) with an EC sub(50) of
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Immnohistochemistry supported the presence of [alpha]1A, [alpha]1B, [alpha]1C, and [alpha]1D Ca channel subunits. Mapping of dihydropyridine-binding sites with DM-BODIPY revealed a distribution of channels over the entire membrane of the Mueller cell with a higher density at the apical region. 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subjects Ambystoma tigrinum
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title High-voltage-activated calcium channels in Mueller cells acutely isolated from tiger salamander retina
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