- 著者
-
林 聖子
岡田 薫
川喜田 健司
- 出版者
- 日本疼痛学会
- 雑誌
- PAIN RESEARCH (ISSN:09158588)
- 巻号頁・発行日
- vol.25, no.1, pp.45-53, 2010-03-15 (Released:2013-06-26)
- 参考文献数
- 24
To investigate underlying mechanism of subjective pain ⁄ numbness sensation following ischemia-reperfusion of upper arm, we examined the changes in skin blood flow (SBF) and current perception threshold (CPT). Eighteen healthy volunteers with informed consents were used. A 140 mm wide tourniquet cuff was inflated to 200 mmHg and maintained for 15 min at non-dominant upper arm. SBF was measured by Laser Doppler flow meter before, during and after ischemia at the index finger. Magnitude of the evoked pain ⁄ numbness sensation after ischemia-reperfusion was recorded by VAS with an electric device continuously. CPT was measured by 5, 250, 2000 Hz of sine-waves randomly applied to the index finger. SBF was increased immediately after reperfusion in all the subjects. Pain ⁄ numbness sensation was also evoked after reperfusion in all subjects.But baseline SBF, increased SBF and magnitude of subjective sensation after reperfusion were different among individuals. Correlation between changes of SBF and magnitude of subjective sensation measured by VAS did not show statistical significance. After ischemia-reperfusion, significant increases of CPT were observed in 250 and 2000 Hz (baseline vs. after reperfusion, p<0.01). The sine-wave stimulation of 5, 250 and 2000 Hz were assumed to activate C, A-delta and A-beta fibers, respectively. The production of pain ⁄ numbness sensation was accompanied with the significant increases of CPT at 250 and 2000 Hz after reperfusion. These results suggest the participation of A fibers in the production of pain ⁄ numbness sensation evoked by ischemia-reperfusion.