Electrophysiological recordings enable the assessment of neuronal excitability, synaptic function, and network activity. Here, we present a protocol for whole-cell patch clamp and extracellular electrophysiology recordings in mouse brain slices. We describe steps for acute brain slice preparation, whole-cell recordings from neurons and astrocytes, and extracellular recordings of compound action potentials and long-term potentiation. We detail procedures for solution preparation, data acquisition, and analysis, with troubleshooting strategies to ensure experimental reliability and reproducibility. For complete details on the use and execution of this protocol, please refer to Wang et al..