烧伤焦痂毒性提取物D_1对培养心肌细胞L-型钙离子通道活动的影响

Effects of the toxic component D 1 extracted from burn eschar on L-type calcium channel of cultured myocardial cells *

目的：研究烧伤焦痂毒性提取物Ｄ１对培养心肌细胞Ｌ－型钙离子通道活动的影响；方法：采用培养２ｄ～５ｄ的大白鼠乳鼠心肌细胞，以Ｃｅｌ－ａｔａｃｈｅｄ方式记录通道电活动；结果：正常大鼠皮肤脂质提取物Ｄ′１在０．５ｍｇ／ｍｌ与１．０ｍｇ／ｍｌ时对钙离子通道活动无显著影响，在２．０ｍｇ／ｍｌ时可使开放活动有所加强；烧伤焦痂毒性提取物Ｄ１在０．５ｍｇ／ｍｌ、１．０ｍｇ／ｍｌ、２．０ｍｇ／ｍｌ时使通道开放活动显著加强，且随着作用量的增加而加强，与正常大鼠皮肤脂质提取物Ｄ′１的作用相差显著，ＳＯＤ可抑制烧伤焦痂毒性提取物对通道活动的影响；结论：烧伤焦痂毒性提取物Ｄ１可激活心肌细胞Ｌ－型钙离子通道，此作用可能是由超氧阴离子介导的。

Objective: To study the effects of the toxic component D 1 extracted form burn eschar on L-type calcium channel of cultured myocardial cells. Methods: The electrical activity of L-type calcium channel was recorded from cell-attached patches of myocardial cells from rats cultured for 2～5 days. Results: D′ 1, a toxic component from normal animal skin, exerted no effects on the electrical activity at 0.5mg/ml and 1.0mg/ml and only exerted effects on it at 2.0mg/ml. However, D 1 significantly activated the channel at 0.5mg/ml, 1.0mg/ml and 2.0mg/ml and its effects on the electrical activity were progressively enhanced with the increase of concentration. The effects could be inhibited by SOD. Conclusion: D 1 can activate L-type calcium channel of cultured myocardial cells, which might be induced by the superoxide anion.