Towards more Physiological Assays: Using High Throughput Automated Patch Clamp for Compound Screening in Primary Hippocampal Neurons

Neuroscience is a notoriously difficult therapeutic area – neuropharmacology programs have the lowest success rate within therapeutic approvals by the FDA. One of the key factors is the dearth of relevant disease models for testing and investigating pathophysiological mechanisms. Dissociated primary mice neurons are excellent modelling systems for neurobiological, biophysical, and pharmacological evaluations. The presence of a wide variety of ion channels and receptors ensures a physiologically relevant analysis of cell response and signaling. To date, patch clamp is the only technique that provides direct functional, temporal and spatial information of a cell’s electrical and signaling properties. In addition, the Qube automated patch clamp (APC) platform enables the possibility of a high throughput screening (HTS) for thousands of compounds by recording 384 cells simultaneously. In this study, isolated primary hippocampal neurons from mice were patched on the Qube 384 APC system. Using an optimized cell dissociation protocol to obtain healthy cell membranes for patch-clamp, we obtained a whole-cell success rate of 65% ± 6.5%. Among these cells, 69% ± 21% expressed sodium (Nav) currents and out of the latter group, 44% ± 6% of cells showed an >100 pA response to 100 µM GABA. Furthermore, action potential firings were recorded from 31% of the cells that passed the quality criteria filtering using the current-clamp mode of the system. Finally, in the GABA-responsive cells, we characterized the effect of 12 GABA receptor modulators on responses to sub-µM GABA concentrations.