Norbury Ryan, Grant Ian, Woodhead Alex, Patterson Stephen D
Faculty of Sport, Technology and Health Sciences, St. Mary's University, Twickenham, Middlesex, UK.
School of Life Sciences, Pharmacy and Chemistry, Kingston University, Kingston, Surry, UK.
Exp Brain Res. 2025 Jan 8;243(1):41. doi: 10.1007/s00221-024-06985-7.
The aim of this study was to assess if ischaemic preconditioning (IPC) can reduce pain perception and enhance corticospinal excitability during voluntary contractions. In a randomised, within-subject design, healthy participants took part in three experimental visits after a familiarisation session. Measures of pressure pain threshold (PPT), maximum voluntary isometric force, voluntary activation, resting twitch force, corticospinal excitability and corticospinal inhibition were performed before and ≥10 min after either, unilateral IPC on the right leg (3 × 5 min); a sham protocol (3 × 1 min); or a control (no occlusion). Pain perception was then assessed in response to a hypertonic saline injection into the vastus lateralis muscle. In the right (occluded) leg, PPT was 10% greater after IPC compared to sham (P = 0.004). PPTs were also 9.5% greater in the contralateral leg for IPC compared to sham (P = 0.031). Maximum voluntary force, voluntary activation and resting twitch force were not different between conditions (all P ≥ 0.133). Measures of corticospinal excitability and inhibition also revealed no significant differences between conditions (all P ≥ 0.240). Hypertonic saline evoked pain revealed no difference in reported intensity or duration between conditions (P ≥ 0.082). IPC can reduce pain sensitivity in local and remote areas but does not subsequently impact neurophysiological measures of excitability or inhibition.
本研究的目的是评估缺血预处理（IPC）是否能在自主收缩过程中降低疼痛感知并增强皮质脊髓兴奋性。在一项随机、受试者自身对照设计中，健康参与者在经过一次熟悉阶段后参加了三次实验性访视。在右侧腿部进行单侧IPC（3×5分钟）、假手术方案（3×1分钟）或对照（不进行阻断）之前及之后≥10分钟，分别测量压力疼痛阈值（PPT）、最大自主等长肌力、自主激活、静息抽搐力、皮质脊髓兴奋性和皮质脊髓抑制。然后通过向股外侧肌注射高渗盐水来评估疼痛感知。在右侧（阻断）腿部，与假手术相比，IPC后PPT提高了10%（P = 0.004）。与假手术相比，IPC时对侧腿部的PPT也提高了9.5%（P = 0.031）。不同条件下的最大自主肌力、自主激活和静息抽搐力无差异（所有P≥0.133）。皮质脊髓兴奋性和抑制的测量结果在不同条件下也无显著差异（所有P≥0.240）。高渗盐水诱发的疼痛在不同条件下报告的强度或持续时间上无差异（P≥0.082）。IPC可降低局部和远处区域的疼痛敏感性，但随后不会影响兴奋性或抑制的神经生理学测量指标。
