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bioRxiv · 10.1101/2023.02.21.529357

A cranial implant for stabilizing whole-cell patch-clamp recordings in behaving rodents

Abstract

BackgroundIn vivo patch-clamp recording techniques provide access to the sub- and suprathreshold membrane potential dynamics of individual neurons during behavior. However, maintaining recording stability throughout behavior is a significant challenge, and while methods for head restraint are commonly used to enhance stability, behaviorally related brain movement relative to the skull can severely impact the success rate and duration of whole-cell patch-clamp recordings. New methodWe developed a low-cost, biocompatible, and 3D-printable cranial implant capable of locally stabilizing brain movement, while permitting equivalent access to the brain when compared to a conventional craniotomy. ResultsExperiments in head-restrained behaving mice demonstrate that the cranial implant can reliably reduce the amplitude and speed of brain displacements, significantly improving the success rate of recordings across repeated bouts of motor behavior. Comparison with existing methodsOur solution offers an improvement on currently available strategies for brain stabilization. Due to its small size, the implant can be retrofitted to most in vivo electrophysiology recording setups, providing a low cost, easily implementable solution for increasing intracellular recording stability in vivo. ConclusionsBy facilitating stable whole-cell patch-clamp recordings in vivo, biocompatible 3D printed implants should accelerate the investigation of single neuron computations underlying behavior.

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Dacre, J., Sanchez-Rivera, M., Schiemann, J., Currie, S., Ammer, J., Duguid, I.. 2023-02-21. A cranial implant for stabilizing whole-cell patch-clamp recordings in behaving rodents. https://doi.org/10.1101/2023.02.21.529357

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