局麻药热增敏效应的体内研究

Investigation of Thermosensitization of Local Anesthetics in vivo

实验用TAⅡ纯系小鼠及其可移植性MA737乳腺癌,观察了局麻药布比卡因和利多卡因的热增敏作用。实验分别用肿瘤生长时间(TGT)和最大平均反应分别评价药物对肿瘤和正常组织热敏性的影响。加温前肿瘤局部注射布比卡固(2mg/0.1ml/只)和利多卡因(2mg/0.1ml/只),均能增大MA737乳腺癌42.5℃的高温反应,前者增强比较高(分别为1.4和1.3),但皮肤的增强比无异(均为1.04)。布比卡因的治疗增强比1.36优于后者的1.23。故而提示,布比卡因较利多卡因能更有选择地增强肿瘤组织的热敏性。同时发现,布比卡因对组织热敏性的影响与治疗温度有关。随温度的升高,从41.5℃,42.5℃到43.5℃,肿瘤增强比提高(ER分别为1.26,1.38和1.52)。但因温度对皮肤的最大平均反应影响较小,因而较高温度43.5℃,治疗增强比较大(1.41)。

The thermosensitizing effect of local anesthetics (Bupivacaine and Lidocaine) on transplanted MA737 mammary carcinoma in inbred mice TA_2 was studied.Tumor Growth Time (TGT) and Average Peak Reaction (APR) were used as indicators to evaluate the thermosensitization effect of local anesthetics on tumor and normal tissue (skin) as well.Both Bupivacaine and Lidocaine injected at dosage of 2mg/0.1ml/mouse intratumorally enhanced thermal response on the tumor xenograft.The TER (Thermal Enhacement Ratio) was 1.4 in the case of Eupivacaine and 1.3 in Lidocaine.Whereas,the TER of the skin was similar for the two agents,around 1.04.Then it was calculated that the TGF (Therapeutic Gain Factor) for Bupivacaine was 1.36 which was higher than that of Lidocaine,1.23.These results showed that Bupivacaine as compared with Lidocaine increased selectively the thermal sensitivity of tumor.The impact of Bupivacaine on thermosensitization of any tissue as demonstrated in our work is related to the intensity of heat applied.With tumor tissue the TERs obtained at heat of 41.5℃,42.5℃ and 43.5℃ for 60 minutes were 1.26,1.38 and 1.52 respectively.