Genetically encoded calcium indicators have proven useful for characterizing dorsal root ganglion neuron excitability in vivo. Challenges persist in achieving high spatial–temporal resolutions in vivo, however, due to deep tissue imaging and motion artifacts that may be limiting technical factors in obtaining measurements. Here we report an ex vivo imaging method, using a peripheral neuron-specific Advillin-GCaMP mouse line and electric field stimulation of dorsal root ganglion tissues, to assess the sensitivity of neurons en bloc. The described method rapidly characterizes Ca²⁺ activity in hundreds of dorsal root ganglion neurons (221 ± 64 per dorsal root ganglion) with minimal perturbation to the in situ soma environment. We further validate the method for use as a drug screening platform with the voltage-gated sodium channel inhibitor, tetrodotoxin. Drug treatment led to decreased evoked Ca²⁺ activity; half-maximal response voltage (EV₅₀) increased from 13.4 V in untreated tissues to 21.2, 23.3, 51.5 (p < 0.05), and 60.6 V (p < 0.05) at 0.01, 0.1, 1, and 10 µM doses, respectively. This technique may help improve an understanding of neural signaling while retaining tissue structural organization and serves as a tool for the rapid ex vivo recording and assessment of neural activity.

基因编码的钙指示剂已被证明可用于表征体内背根神经节神经元的兴奋性。然而，由于深层组织成像和运动伪影可能限制获得测量的技术因素，在体内实现高时空分辨率仍然存在挑战。在这里，我们报告了一种离体成像方法，使用外周神经元特异性 Advillin-GCaMP 小鼠系和背根神经节组织的电场刺激，以评估神经元整体的敏感性。所述方法快速表征数百个背根神经节神经元（每个背根神经节 221 ± 64）中的 Ca ²⁺活性，对原位体细胞环境的干扰最小。我们进一步验证了该方法可用作电压门控钠通道抑制剂河豚毒素的药物筛选平台。药物治疗导致Ca ²⁺诱发活性降低；在 0.01、0.1、1 和 10 µM剂量下，半最大响应电压 (EV ₅₀ ) 从未处理组织中的 13.4 V 增加到 21.2、23.3、51.5 ( p < 0.05) 和 60.6 V ( p < 0.05) ， 分别。该技术可能有助于提高对神经信号传导的理解，同时保留组织结构组织，并可作为快速离体记录和评估神经活动的工具。