摘要
目的研究三氯乙烯(TCE)对体外培养的人角质形成细胞(KC)一氧化氮(NO)合成和一氧化氮合酶(NOS)表达及活力的影响,探讨TCE的皮肤细胞毒性机制。方法无血清培养的正常人KC与0.125、0.25、0.5、1.0、2.0mmol/L的TCE共培养4h,分别于染毒后12、24、48、72h测定培养液中NO含量和NOS活力,分析其时间—剂量—效应关系,并用逆转录-聚合酶链反应(RT-PCR)法检测诱导型NOS(iNOS)mRNA的表达情况。结果低剂量组(0.125和0.25mmol/L)NO含量与iNOS活力在染毒后各时点与对照组相比均无差异;0.5mmol/L组NO含量与iNOS活力均在染毒后48h开始升高,分别为(32.19±4.75)μmol/L[对照组:(23.70±3.11)μmol/L,P<0.05]和(1.15±0.02)×103U/L[对照组:(0.77±0.06)×103U/L,P<0.05],随着染毒浓度的升高,0.5～2.0mmol/L组NO量与iNOS活力呈上升趋势,而且上升出现的时间提前,1.0和2.0mmol/L组分别于染毒后24和12h出现升高;NO释放的增加总是与iNOS活力升高一致,而结构型NOS(cNOS)活力在各剂量组的各时点均无变化;RT-PCR结果显示TCE可以诱导iNOSmRNA转录水平增高。结论TCE可以诱导人角质形成细胞NO合成增加,大量产生的NO与iNOS基因的上调有关,这一机制可能参与了TCE的皮肤细胞毒性。
Objective To observe the changes of nitric oxide（NO） and nitric oxide synthase （NOS）in cultured normal human keratinocytes after treated with trichloroethylene（TCE） and further explore the dermatotoxicity mechanism of TCE. Methods Normal human keratinocytes were cultured in serum-free medium and treated with 0. 125,0.25,0. 5,1.0 or 2. 0 mmol/L of TCE for 4,12,24,48 and 72 hours after stimulation, the content of NO and the activity of NOS （inducible-NOS and constitutive-iNOS） were detected to analysis time-dose-effect relationship. Meanwhile, RT-PCR was applied to determine the expression of iNOS mRNA. Results Both NO production and iNOS activity did not change at the concentration of 0. 125 mmol/L and 0.25 mmol/L in any time point after stimulation, they began to elevate 48 hours after stimulated with 0.5mmol/L of TCE [ （32. 19 ±4. 75） μmol/L compared with the control group： （23.70 ±3. 11 ） μmol/L, P 〈 0. 05 ,and（ 1.15 ±0.02） × 10^3 U/L compared with the control group： （0. 77 ±0.06） × 10^3 U/L,P 〈 0.05, respectively] ,displaying a trend of increase and ahead of time along with the increase of TCE concentration. NO release was consistent with the elevation of iNOS activity but not eNOS ; RT-PCR also showed an over-expression of iNOS mRNA after TCE stimulation. Conclusion Dose-dependently and time-relatedly, TCE can induce keratinocytes to generate large amount of NO which attributes to the up-regulation of iNOS, and all this may contribute to the eytotoxieity and dermato-toxieity of TCE.
出处
《中国职业医学》
CAS
北大核心
2006年第5期329-332,共4页
China Occupational Medicine
基金
国家自然科学基金资助项目(No.30471469)
安徽省高校省学术技术带头人后备人选科学研究资助重点项目(No.2005hbz17zd)
安徽省人才开发资金资助项目(No.2004Z032)
