title: Improved throughput of PatchXpress hERG assay using intracellular potassium fluoride.
abstract: Blockade of the human ether-a-go-go-related gene (hERG) potassium channel, with a consequent possibility of QT prolongation and increased susceptibility to a characteristic polymorphic ventricular arrhythmia, torsade de pointes, is an important cause of withdrawal of drugs from the market. In the aftermath of recent drug withdrawals, regulatory agencies now require in vitro hERG screening of all pharmaceutical compounds that are targeted for human use. To minimize the potential for failure in later-stage drug development, many pharmaceutical and biotechnology companies have begun to use automated patch clamp systems with higher throughput than conventional manual patch-clamp techniques to conduct routine functional hERG screening during drug discovery and early development. We have optimized an automated patch-clamp hERG screening method for the PatchXpress 7000A system (Molecular Devices, Sunnyvale, CA) using potassium fluoride (KF) in the internal recording solution. In this study we show that (1) the biophysical and pharmacological properties of hERG current recorded with KF are similar to those with standard potassium chloride solutions, (2) use of KF significantly improves the success rate of hERG screening using PatchXpress without compromising data quality, and (3) utilization of KF can significantly increase the throughput of hERG screening with PatchXpress.
authors.affiliation: Merck Research Laboratories, West Point, PA 19486, USA. haoyu_zeng@merck.com
authors.forename: Haoyu
authors.initials: H
authors.lastname: Zeng
authors.forename: Jacob R
authors.initials: JR
authors.lastname: Penniman
authors.forename: Fumi
authors.initials: F
authors.lastname: Kinose
authors.forename: David
authors.initials: D
authors.lastname: Kim
authors.forename: Elena S
authors.initials: ES
authors.lastname: Trepakova
authors.forename: Manish G
authors.initials: MG
authors.lastname: Malik
authors.forename: Spencer J
authors.initials: SJ
authors.lastname: Dech
authors.forename: Bharathi
authors.initials: B
authors.lastname: Balasubramanian
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Salata
mesh_terms: D000818:Animals; D016466:CHO Cells; D002462:Cell Membrane / Q000187:drug effects; D006224:Cricetinae; D003412:Cricetulus; D003627:Data Interpretation, Statistical; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D004594:Electrophysiology; D051638:Ether-A-Go-Go Potassium Channels / Q000187:drug effects*; D005459:Fluorides; D018408:Patch-Clamp Techniques / Q000379:methods*; D026902:Potassium Channel Blockers / Q000494:pharmacology*; D017680:Potassium Compounds
chemical_list: D051638:Ether-A-Go-Go Potassium Channels; D026902:Potassium Channel Blockers; D017680:Potassium Compounds; C033320:potassium fluoride; D005459:Fluorides