Abstract
Fast (‘concentration jump’) applications of neurotransmitters are crucial for screening studies on ligand-gated ion channels. In this paper, we describe a method for automated fast perfusion of neurotransmitters (or drugs) during two-microelectrode voltage-clamp experiments on Xenopus oocytes. The oocytes are placed in a small bath chamber that is covered by a glass plate with two channels for the microelectrodes that are surrounded by a quartz funnel serving as a reservoir for test solutions. The oocytes are perfused in a vertical direction via the two channels in the plate. Automation of compound delivery is accomplished by means of a programmable pipetting workstation. A mean rise time for 10–90% current increase through muscle-type nACh channels of 55.0±1.3 ms (30 μM acetylcholine) was estimated. Automation, fast perfusion rates, and economical use of compounds (≈100 μl/data point) make the system suitable for screening studies on ligand- and voltage-gated ion channels.
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We thank Prof. E. N. Timin for his helpful comments. Supported by FWG grant 15914.
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Baburin, I., Beyl, S. & Hering, S. Automated fast perfusion of Xenopus oocytes for drug screening. Pflugers Arch - Eur J Physiol 453, 117–123 (2006). https://doi.org/10.1007/s00424-006-0125-y
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DOI: https://doi.org/10.1007/s00424-006-0125-y