Chronic skeletal muscle pain and regeonal hemodynamic abnormality

1)冷加压试验（CPT）对静息咬肌血流动力学的影响由于CPT被报道引起人骨骼肌中肌交感神经活动的增加（维克托等，1987），通过使用近红外光谱装置测量CPT诱导的静息人咬肌中的血流动力学变化。结果：CPT引起肌内血容量和氧饱和度水平显著增加。此外，在停止4 ℃ CPT任务后，显示出明显的反弹性Hb降低。2）α和β肾上腺素能受体阻滞剂对肌肉血流动力学的影响本研究评价了静脉输注非选择性α和β肾上腺素能受体阻滞剂对咬肌血流动力学的影响。结果如下：肌内血容量和氧饱和度水平在静脉输注α受体阻滞剂后显著增加，而在静脉输注β受体阻滞剂后有降低的趋势。3）健康受试者和慢性肩肌痛受试者对CPT的血流动力学反应的比较本研究确定了正常和慢性肩肌痛受试者在CPT期间上肌区血容量的差异。两组受试者CPT时平均血容量均高于基线值，而疼痛组CPT时平均血容量明显低于基线值，提示肌内血流动力学异常可能与慢性肌肉疼痛的病理生理有关。

1) Effect of cold pressor test (CPT) on resting masseter muscle hemodynamics.Since CPT was reported to evoke an increase of muscle sympathetic nerve activity in the human skeletal muscle (Victor et al.1987), CPT-induced hemodymanic change in the resting human masseter muscle was measured by using a near infrared spectroscopy device. Results : CPT induced strong increase in intramuscular blood volume and oxygen saturation levels. Moreover, after cessation of 4 degree C CPT task clear rebound Hb decrease was demonstrated. Therefore it can be speculated that increase in muscle sympathetic nerve activity induces hyperemia in normal subjects.2) Effect of alpha and beta adrenergic blocking agents on intramuscular hemodynamic changes.This study evaluated that the effect of intravenous infusion of non-selective alpha- and beta-adrenergic blocking agents on masseter muscle hemodynamics. Results : Intramuscular blood volume and oxygen saturation levels significantly increased by intravenous infusion of alpha blocking agent and trended to decrease by beta blocking agent.3) Comparison of hemodynamic response to CPT between healthy subjects and chronic trapezius muscle pain subjects.This study determined the difference in blood volume of the upper trapezius muscle area between normal and chronic shouder muscle pain subjects during CPT.Results : In both group of subjects the mean blood volume increased above the baseline livel during CPT,however, pain subjects exibited significantly lower mean blood volume during CPT.These results suggest that intramuscular hemodynamic abnormality might be related to the chronic muscle pain pathophysiology.