中文摘要：

目的研究2，3，7，8-四氯二苯并二噁英（TCDD）染毒对表皮细胞芳香烃受体（AhR）和转化生长因子（TGF-α）表达的影响。方法利用半定量逆转录PCR技术（RT-PCR）对24hTCDD染毒组进行AhR和TGF-α基因表达的测定，并分析两者之间的相互关系。结果以β-aetin为内参照，测定细胞中AhR和TGF-α mRNA表达的相对含量。结果显示随着TCDD浓度的增高，细胞中AhR mRNA的相对表达量呈现下降的趋势，r=-0．548，各染毒组与对照组相比差异有统计学意义（F=4．124，P=0．021），两两比较7×10^-10mol／L组（0．0620±0．0085）和7×10^-9mol／L组（0．0518±0．0194）与对照组（0．1138±0．0227）之间的差别有统计学意义（t=-3．48，P〈0．05；t=-4．17，P〈0．01），且其相对表达量分别为对照组的55％和45％。TGF-α mRNA的相对表达量随浓度的增加则呈现上升的趋势，相关系数r=0．695（P〈0．01），各组之间差异有统计学意义（F=15．789，P=0．000），在7×10^-10mol／L组（0．1474±0．0390）和7×10^-9mol／L组（0．2133±0．0364）相对表达量与对照组（0．0561±0．0100）的差别具有统计学意义（t=4．49，P〈0．01；t=7．74，P〈0．01），且其相对表达量是对照组的2．6倍和3．8倍。同时对AhR与TGF-α mRNA相对表达水平进行相关分析，两者呈负相关，r=-0．561（P〈0．05）。结论TCDD对细胞增殖过程中可影响基因表达，AhR表现为下调，TGF-α表现为上调，且两基因表达量之间存在负相关关系。

英文摘要：

Objective To study HaCaT-keratinocyte cell lines, a chosen model of human epidermis in an attempt to analyze the mRNA expression of AhR and TGF-α induced by TCDD Methods Semi-quantitative reverse transcription PCR-technique was used for assaying the relative levels of AhR and TGF-α mRNA of HaCaT-cells during the proliferation period when the cells were cultured for 24 hours. Results Relative level of the AhR-transcripts （corrected with β-actin ） decreased with the elevated concentration of TCDD and the relevant coefficient between the proliferation rate and concentration was -0. 548, and the differences among all groups were significant （F = 4. 124, P = 0. 021 ）. The vehicle control was respectively compared with 7 × 10^-10 tool/L（0. 0620 ± 0. 0085 ） and 7 × 10^-9 mol/L（0. 0518 ± 0. 0194 ） group, significantly different from the control group （0. 1138 ± 0. 0227 ） （ t = - 3.48, P 〈 0. 05 ; t = -4. 17 ,P 〈0. 01 ）, the expression amount being 55% and 45% of the control. Relative levels of TGF-α mRNA tended to increase with the elevated concentration with the significant coefficient of 0. 695 （ P 〈 0. 01 ） , and the differences among all groups were significant （ F = 15. 789, P = 0. 000 ） . In two higher concentration group 7 × 10^-10 mol/L （ 0. 1474 ± 0. 0390 ） and 7 × 10^-9 mol/L （ 0. 2133 ± 0. 0364 ） , their relative expression amount of TGF-α mRNA was 2.6-fold, 3.8-fold of the control group （0. 0561 ± 0. 0100 ） respectively. Further analysis for the relevant relationship between the amounts of the AhR mRNA and TGF-α mRNA showed a highly negative correlation, the coefficient being -0. 561 （P 〈 0. 05 ）. Conclusions TCDD down-regulate the expression of AhR and up-regulate the expression of TGF-α A strong negative correlation between AhR and TGF-α expression is found.