镉对中国仓鼠成纤维细胞活力和缝隙连接通讯功能的影响

Effects of cadmium chloride on the viability and gap junctional intercellular communication level of Chinese hamster lung fibroblasts

目的 探讨致癌物镉对中国仓鼠肺成纤维细胞（Ｃｈｉｎｅｓｅ ｈａｍｓｔｅｒ ｌｕｎｇ ｆｉｂｒａｂｌａｓｔｓ，ＣＨＬＦ） 缝隙连接通讯（ｇａｐ ｊｕｎｃｔｉｏｎａｌｉｎｔｅｒｃｅｌｌｕｌａｒｃｏｍ ｍｕｎｉｃａｔｉｏｎ ，ＧＪＩＣ） 功能的影响。方法 细胞毒性实验采用常规的噻唑蓝（ ＭＴＴ） 法，同时观察显微镜下细胞形态的变化。细胞ＧＪＩＣ 水平用划痕标记染料示踪（ＳＬＤＴ）技术测定。结果 ＣｄＣｌ２ 染毒２４ 小时和１２ 小时对ＣＨＬＦ 活力的半数抑制浓度ＩＣ５０ 分别为２０ ．８ μｍｏｌ／Ｌ和０ ．１５ ｍ ｍｏｌ／Ｌ。ＣｄＣｌ２ 在不产生明显细胞毒性的浓度下即可抑制ＣＨＬＦ 的ＧＪＩＣ 功能，该作用具有一定的剂量时间效应关系。细胞持续接触低浓度ＣｄＣｌ２ 一定时间后，受抑的ＧＪＩＣ 有恢复倾向，而在出现明显细胞毒性的情况下，ＧＪＩＣ 抑制是不可逆的。结论 ＧＪＩＣ 功能抑制可能在镉化合物致癌过程中起了一定的作用。

Objective To investigate effect of the carcinogen cadmium chloride (CdCl 2) on gap junctional intercellular communication (GJIC) level of Chinese hamster lung fibroblasts(CHLF). Methods The cytotoxicity of CdCl 2 was determined with the MTT assay,the microscopic morphology of CHLF was observed as well.GJIC level of CHLF was studied using the scrape loading and dye transfer (SLDT) method. Results The 50% inhibitory concentrations of 24 h and 12 h exposure were 20.8 μmol/L and 0.15 mmol/L,respectively.CdCl 2 was able to inhibit GJIC of CHLF from the noncytotoxic dose levels and a dose time effect relationship of this action was observed.The inhibited GJIC recovered to some degree after a prolonged exposure but the inhitibion was irreversible at relatively high dose level with significant cytotoxicity. Conclusion The inhibition of GJIC may have certain effect on the carcinogenesis of cadmium compounds. Key words Cadium Cytotoxicity GJIC? ａｃｔｉｖａｔｉｏｎ ｏｆ ＰＢＭＣ． Ｔｈｅ ｅｆｆｅｃｔｓ ｄｅｐｅｎｄ ｏｎ ｔｈｅ ｃｏｎｃｅｎｔｒａｔｉｏｎ ｏｆ ｒｅｔｉｎｏｉｄｓ． ＷＴ