白细胞介素－2镇痛功能位点的研究

The Analgesic Domain of Interleukin-2.Xu Di.Jiang Chunlei,Zheng Zhongcheng,FanPeifang.

白细胞介素－２（ＩＬ－２）是重要的免疫调节因子，近来发现还有中枢镇痛作用，用不同ＩＬ－２突变体测定其对大鼠痛阈的影响，发现完全丧失免疫刺激作用的２０Ｌｅｕ－ＩＬ－２（２０Ａｓｐ→Ｌｅｕ）仍能显著提高大鼠的痛阈，其作用强度与天然ＩＬ－２无显著差异，而另一突变体４５Ｖａｌ－ＩＬ－２（４５Ｔｙｒ→Ｖａｌ）虽保留免疫学活性却不能提高大鼠的痛阈。这些结果证明ＩＬ－２分子中具有镇痛作用与具有免疫作用的功能位点是相互独立的；ＩＬ－２分子中第４５位Ｔｙｒ对ＩＬ－２镇痛作用的发挥起重要作用。

nterleukin-2(IL-2)is an important immuneregulator.Recently it is found that IL-2 is alsoan analgesic molecule.Using the potassiumiontophoresis as pain stimulus to induce tail-flick and taking the intensity of current (mA)at the moment of the response as the painthreshold (PT),it is reported that mutant 20Leu-IL-2 (20Asp-Leu),which could not bindto the βsubunit of IL-2 receptor and thus hadno immune activity, could increase the PT ofthe rats, indicating that the analgesic and theimmunal functions be related to two differentdomains in IL-2 molecule. Mutant 45Val-IL-2(45Tyr-Val),which had immunal activity,had no analgesic effet,suggesting that the45Tyr be crucial for the analgesic effect of IL-2and the analgesic domain be located around the45Tyr.