Recent studies have demonstrated that muscle sympathetic nerve activity (MSNA) responses to isometric exercise differs between active and inactive limbs. Whether limb-dependent responses are characteristic of responses to the cold pressor test (CPT) remains to be established. Therefore, we tested the hypothesis that CPT-induced MSNA responses differ between affected and unaffected limbs such that MSNA in the affected lower limb is greater than MSNA responses in the contralateral lower limb and the upper limb. Integrated peroneal MSNA (microneurography) was measured in young healthy individuals (n = 10) at rest and during three separate 3-min CPTs: the microneurography foot, opposite foot, and opposite hand. Peak MSNA responses were extracted for further analysis, as well as corresponding hemodynamic outcomes including mean arterial pressure (MAP; Finometer). MSNA responses were greater when the microneurography foot was immersed in ice water than when the opposite foot was immersed (38 ± 18 vs 28 ± 16 bursts/100hb: P < 0.01). MSNA responses when the opposite hand was immersed were greater than both the microneurography foot (46 ± 22 vs 38 ± 18 bursts/100hb: P < 0.01) and opposite foot (46 ± 22 vs 28 ± 16 bursts/100hb: P ≤0.01). Likewise, MAP responses were greater during the hand CPT than the microneurography foot (99 ± 9 vs 96 ± 8 mmHg: P < 0.01) and opposite foot CPT (99 ± 9 vs 96 ± 9 mmHg: P < 0.01). These data indicate that (a) upper limbs and (b) immersed limbs elicit greater MSNA responses to the CPT than lower and/or non-immersed limbs.

最近的研究表明，活跃肢体和不活跃肢体之间的肌肉交感神经活动（MSNA）对等长运动的反应有所不同。肢体依赖性反应是否是冷加压试验（CPT）反应的特征仍有待确定。因此，我们测试了以下假设：CPT 诱导的 MSNA 反应在受影响和未受影响的肢体之间存在差异，因此受影响下肢的 MSNA 大于对侧下肢和上肢的 MSNA 反应。在年轻健康个体 ( n  = 10) 休息时和三个单独的 3 分钟 CPT 期间测量综合腓骨 MSNA（显微神经造影） ：显微神经造影脚、对侧脚和对侧手。提取 MSNA 峰值响应以及相应的血流动力学结果（包括平均动脉压（MAP；Finometer））以供进一步分析。当显微神经造影脚浸入冰水中时，MSNA 反应比另一只脚浸入时更大（38 ± 18 vs 28 ± 16 爆发/100hb：P  < 0.01）。当另一只手浸入水中时，MSNA 反应大于显微神经造影脚（46 ± 22 vs 38 ± 18 突发/100hb：P  < 0.01）和另一只脚（46 ± 22 vs 28 ± 16 突发/100hb：P  ≤ 0.01） 。同样，手部 CPT 期间的 MAP 反应高于足部显微神经造影（99 ± 9 vs 96 ± 8 mmHg：P  < 0.01）和对侧足部 CPT（99 ± 9 vs 96 ± 9 mmHg：P < 0.01）。这些数据表明，(a) 上肢和 (b) 浸没的肢体比下肢和/或非浸没的肢体对 CPT 产生更大的 MSNA 反应。