Assessing hERG channel inhibition using PatchXpress

PatchXpress, an automated 16-channel parallel patch clamp system, was used to determine inhibition of human ether-a-go-go related gene (hERG) potassium channels by known blockers. A monoclonal cell line stably expressing hERG potassium channels was generated in CHO-K1 cells. Results were compared to conventional patch clamp experiments using similar voltage protocols and solutions. Success rates were evaluated for cell recordings under a variety of conditions, including Accumax versus trypsin treatment to harvest cells, single versus double compound additions, and polystyrene versus glass-coated compound plates. Finally, polystyrene versus glass-coated compound plates were evaluated, and the authors found that for some compounds (but not all), preparation of compound samples in glass-coated plates resulted in inhibition that more closely matched data obtained by conventional experiments.