Purchase this article with an account.
O. Strauss, M.O. Karl, S. Wimmers; Different Outwardly Recifying Potassium Currents in the Mouse Retinal Rigment Epithelium . Invest. Ophthalmol. Vis. Sci. 2005;46(13):3042.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: The retinal pigment epithelium (RPE) supports the normal function of the photoreceptors. By transporting ions, metabolites, and water it helps to maintain an appropriate microinvironment for the function photoreceptors. Large potassium conductances in the RPE are directly and indirectly involved in these transport mechanisms. Methods: Cultured mouse RPE cells were investigated by means of the patch–clamp technique. Results: Mouse RPE expresses two distinct outwardly rectifying potassium conductances, one of them activates at potentials positive to –10 mV and shows no inactivation. This current was sensitive to 10 nM agitoxin–2 (reduction to 30,5%) supporting the idea that it is carried by a potassium channel of the Kv1.x family. Additionally, we found an outwardly rectifying potassium current which activates at potentials more positive to –60 mV with slow inactivation at very positive potentials. This current was half–maximally activated at –35 mV. Conclusions: The molecular correlate of these potassium conductances is not yet identified. Because of its negative activation threshold this channel is open at physiological potentials and may contribute to different aspects of the RPE transport physiology.
This PDF is available to Subscribers Only