铬、汞、镉、镍四种重金属化合物对FL/P4501A1细胞酶活性的影响

EFFECTS ON THE ENZYME ACTIVITIES OF FOUR KIND OF HEAVY METAL COMPOUNDS(Cr 3+ ,Hg 2+ ,Cd 2+ ,Ni 2+ ) IN FL/1A1 CELLS

利用不同浓度的重金属化合物溴化汞、三氯化铬、硫酸镉、氯化镍处理人羊膜ＦＬ／Ｐ４５０１Ａ１细胞，其半数抑制浓度（ＩＣ５０，ｍｇ／ｍｌ）分别为６．０２６０，３７．５２１３，２４．５４９１和４５．３８４５。结果表明：不同的重金属化合物对ＦＬ／Ｐ４５０１Ａ１细胞的毒性相差很大，溴化汞和硫酸镉的细胞毒性较大。ＦＬ／Ｐ４５０１Ａ１细胞带有Ｐ４５０１Ａ１基因，该基因产物为乙氧基异吩恶唑Ｏ—去乙基酶（ｅｔｈｏｘｙｒｅｓｏｒｕｆｉｎＯ－ｄｅｅｔｈｙｌａｓｅ，ＥＲＯＤ）。酶活性测定结果表明溴化汞、硫酸镉能抑制ＦＬ／１Ａ１细胞自发产生的ＥＲＯＤ活性；三氯化铬、溴化汞、氯化镍、硫酸镉能抑制去甲肾上腺素诱导ＦＬ／１Ａ１细胞产生的ＥＲＯＤ活性。Ｐ４５０１Ａ１酶能激活多环芳烃，溴化汞和硫酸镉可通过降低Ｐ４５０１Ａ１酶活性干扰多环芳烃的致癌作用。

Human amnion FL/P4501A1 cells were treated with various heavy metal compounds(HgBr 2,CrCl 3,CdSO 4,NiCl 2);the 50% inhibitory concentrations(IC 50 ,mg/ml) of HgBr 2,CrCl 3,CdSO 4,NiCl 2 were 6.0260,37.5213,24.5491,45.3845 respectively.The results showed that the cell toxicities of these heavy metal compounds on FL/P450 1A1 cell are different.The cell toxicities of HgBr 2 and CdSO 4 are more serious.FL/P450 1A1 cell carries P450 1A1 gene,the gene can produce ethoxyresorufin O-deethylase(EROD).The results of this enzyme activity assay show HgBr 2 and CdSO 4 can inhibit uninduced FL/P450 1A1 cell EROD activity;CrCl 3,HgBr 2,NiCl 2 and CdSO 4 can inhibit FL/P450 1A1 cell EROD activity induced by norepinephrine.P4501A1 enzyme can activate polycyclic aromatic hydrocarbons(PAHs),HgBr 2 and CdSO 4 may decrease the enzyme activity and interfere with the carcinogenesis of PAHs.