Jonzon B, Sylvén C, Kaijser L
Department of Clinical Pharmacology and Internal Medicine, Huddinge Hospital, Sweden.
Cardiovasc Res. 1989 Sep;23(9):807-9. doi: 10.1093/cvr/23.9.807.
To study the hypothesis that endogenous adenosine is a mediator of the ischaemic pain sensation, the effect of the adenosine receptor blocker theophylline (5.5 mg of the ethylendiamine salt.kg-1 intravenously) was tested in a placebo controlled double blind cross over study (placebo/theophylline/placebo or placebo/placebo/theophylline) in five healthy volunteers. Ischaemic work was performed with a spring loaded hand ergometer (1 Hz). The pain sensation was continuously reported using the Borg scale. Blood flow was measured by occlusion plethysmography. Pain was reported 18 (SEM 2.4) s after starting the ischaemic work and increased continuously to a maximum after 129(18) s (placebo). Theophylline at a plasma concentration of 75(7) mumol.litre-1 decreased the pain sensation in relation to working time. With theophylline, 12(3)% more work (p less than 0.01) was performed for the same reported pain estimate. Blood flow increased from a basal level of 52(9) to 495(55) ml.min-1.100 ml-1 30 s after work and returned to normal within 30-40 min. Theophylline did not affect blood flow. In conclusion, theophylline has a small but significant inhibitory effect on the ischaemic pain sensation compatible with a hyperalgesic effect of adenosine.
为了研究内源性腺苷是缺血性疼痛感觉介质这一假说，在一项安慰剂对照双盲交叉研究（安慰剂/茶碱/安慰剂或安慰剂/安慰剂/茶碱）中，对五名健康志愿者测试了腺苷受体阻滞剂茶碱（5.5毫克乙二胺盐·千克⁻¹静脉注射）的作用。使用弹簧加载式手部测力计（1赫兹）进行缺血性工作。使用博格量表持续报告疼痛感觉。通过阻断体积描记法测量血流量。在开始缺血性工作后18（标准误2.4）秒报告疼痛，并在129（18）秒后持续增加至最大值（安慰剂）。血浆浓度为75（7）微摩尔·升⁻¹的茶碱相对于工作时间降低了疼痛感觉。使用茶碱时，在相同报告的疼痛估计下，完成的工作量增加了12（3）%（p<0.01）。血流量从基础水平52（9）增加到工作后30秒时的495（55）毫升·分钟⁻¹·100毫升⁻¹，并在30 - 40分钟内恢复正常。茶碱不影响血流量。总之，茶碱对缺血性疼痛感觉有微小但显著的抑制作用，这与腺苷的痛觉过敏作用相符。
