Multiple Two-Photon Targeted Whole-Cell Patch-Clamp Recordings From Monosynaptically Connected Neurons in vivo

Area of Science:

• Neuroscience
• Electrophysiology

Background:

• In vitro studies provide extensive data on mammalian nervous system connectivity, but in vivo data remains limited.
• Simultaneous recording of subthreshold responses and evoked action potentials in closely located neurons in vivo is technically challenging.

Purpose of the Study:

• To present a detailed protocol for in vivo two-photon targeted multiple whole-cell patch clamp recordings.
• To enable the study of monosynaptic inputs and correlated neuronal activity in superficial cortical layers.

Main Methods:

• Developed a novel setup for in vivo two-photon targeted multiple (2-4) whole-cell patch clamp recordings.
• Detailed surgical procedures, pipette preparation, and recording acquisition in anesthetized mouse primary somatosensory cortex.
• Included in vivo and post hoc histological verification.

Main Results:

• The described procedure takes approximately 4 hours from surgery start to recording completion.
• Enables examination of electrophysiological features of unitary excitatory and inhibitory monosynaptic inputs.
• Facilitates investigation into synaptic mechanisms underlying correlated neuronal activity during different brain states.

Conclusions:

• This technique overcomes technical limitations for in vivo electrophysiological recordings of nearby neurons.
• Provides a valuable tool for advancing our understanding of neural circuit function in mammals.
• Opens new avenues for studying synaptic integration and network dynamics in vivo.