Teng Yi, Zou Xian, Liu Jin, Hu Xiangyu, Zhou Cheng, Ou Mengchan
Department of Anesthesiology, West China Hospital of Sichuan University, Chengdu, China.
Research Center of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China.
Sci Rep. 2025 Jul 20;15(1):26349. doi: 10.1038/s41598-025-12201-5.
Sensory-selective nerve blockade is highly useful for pain management in clinical practice, but developing such blockers remains challenging. A major handicap is the lack of objective in vivo animal models to evaluate motor and sensory nerve conduction simultaneously. Due to anatomical structures, motor evoked potentials (MEPs) and/or somatosensory evoked potentials (SSEPs) may be used to assess nerve conduction. MEPs were elicited by stimulating motor cortex and recorded from contralateral hind limb. SSEPs were generated by stimulating sciatic nerve and recorded from contralateral sensory cortex. Amplitude/latency changes were recorded under various physiological conditions (e.g., anesthesia, durations, temperatures, and oxygen) and drug interventions for validation. Compared to sevoflurane, propofol minimally inhibited MEPs at sedative doses and was therefore used during recordings. Both hypothermia (34-36 °C) and hyperthermia (38-40 °C) significantly suppressed MEP and SSEP amplitudes (P < 0.0001). Reduced oxygen saturation (SaO) decreased MEP amplitudes (P < 0.0001), and the amplitudes were strongly correlated with SaO (R = 0.8284). For selective blockade validation, lidocaine suppressed both MEP and SSEP amplitudes below 20% of baseline (P < 0.0001), confirming non-selectivity. In contrast, QX-314/capsaicin selectively suppressed SSEPs (P < 0.0001), while MEPs remained stable. This model is stable for evaluating selective nerve blockade in vivo for at least 60 min under controlled physiological conditions.
感觉选择性神经阻滞在临床实践中对疼痛管理非常有用，但开发此类阻滞剂仍然具有挑战性。一个主要障碍是缺乏用于同时评估运动和感觉神经传导的客观体内动物模型。由于解剖结构的原因，可以使用运动诱发电位（MEP）和/或体感诱发电位（SSEP）来评估神经传导。通过刺激运动皮层引出MEP，并从对侧后肢进行记录。通过刺激坐骨神经产生SSEP，并从对侧感觉皮层进行记录。在各种生理条件（如麻醉、持续时间、温度和氧气）和药物干预下记录幅度/潜伏期变化以进行验证。与七氟醚相比，丙泊酚在镇静剂量下对MEP的抑制作用最小，因此在记录过程中使用。低温（34 - 36°C）和高温（38 - 40°C）均显著抑制MEP和SSEP幅度（P < 0.0001）。氧饱和度（SaO）降低会降低MEP幅度（P < 0.0001），且幅度与SaO密切相关（R = 0.8284）。为了验证选择性阻滞，利多卡因将MEP和SSEP幅度均抑制至基线的20%以下（P < 0.0001），证实其无选择性。相比之下，QX - 314/辣椒素选择性抑制SSEP（P < 0.0001），而MEP保持稳定。在受控的生理条件下，该模型在体内评估选择性神经阻滞至少60分钟是稳定的。
