McCormack K, Kidd B L, Morris V
Drug Research Group, McCormack Limited, Leighton Buzzard, UK.
Eur J Clin Pharmacol. 2000 Sep;56(6-7):459-62. doi: 10.1007/s002280000132.
To develop a reliable assay for quantifying the analgesic efficacy of non-steroidal anti-inflammatory drugs (NSAIDs) using a model that is accepted as a paradigm of clinical pain.
Fifteen normal subjects, all of whom were volunteers from medical school staff, took part in the study.
Capsaicin (20 microl) in solution (0.03 mg/ml) was applied to the volar surface of the forearm, and the skin was maintained at a constant temperature using a thermal stimulator. The magnitude of the surrounding area of mechanical allodynia to a brush stimulus (i.e. a clinical correlate of tenderness to touch) was assessed. Under double-blind, placebo-controlled conditions, the test was repeated using skin previously treated with ibuprofen gel or placebo.
A close linear relationship was observed between skin temperature over a range of 30 degrees C to 40 degrees C and the area of capsaicin-induced allodynia. Ibuprofen gel significantly reduced (P < 0.004) the area of touch-evoked allodynia at a constant skin temperature of 40 degrees C.
The thermal-facilitated adaptation of the capsaicin model described in this study represents an inexpensive and reliable assay for the effects of topical formulations of NSAID upon mechanical sensitivity. As such, it is a potential alternative to many clinical studies in which inherent confounding and bias can preclude a meaningful conclusion.
使用一种被公认为临床疼痛范例的模型，开发一种可靠的方法来量化非甾体抗炎药（NSAIDs）的镇痛效果。
15名正常受试者，均为医学院工作人员中的志愿者，参与了该研究。
将辣椒素（20微升）溶液（0.03毫克/毫升）涂抹在前臂掌侧表面，并用热刺激器将皮肤维持在恒定温度。评估对刷擦刺激的机械性异常性疼痛周围区域的大小（即对触摸压痛的临床相关指标）。在双盲、安慰剂对照条件下，使用先前用布洛芬凝胶或安慰剂处理过的皮肤重复该测试。
在30摄氏度至40摄氏度的温度范围内，观察到皮肤温度与辣椒素诱导的异常性疼痛区域之间存在密切的线性关系。在皮肤温度恒定为40摄氏度时，布洛芬凝胶显著降低了（P < 0.004）触摸诱发的异常性疼痛区域。
本研究中描述的辣椒素模型的热促进适应性代表了一种廉价且可靠的方法，用于评估NSAID局部制剂对机械敏感性的影响。因此，它是许多临床研究的潜在替代方法，在这些临床研究中，固有的混杂因素和偏差可能会妨碍得出有意义的结论。
