大鼠BPDE-DNA加合物生成及其高效液相色谱测定

目的 研究苯并(a)芘(BaP)诱导大鼠产生(7R,8S)-二羟基-(9S,10R)-环氧-7,8,9,10-四氢苯并(a)芘(BPDE)-DNA加合物的生成.建立以血液为样品的检测染毒大鼠BPDE-DNA加合物的高效液相色谱法.方法 选用清洁级SD大鼠,一次性腹腔注射苯并(a)芘二甲基亚砜溶液(以1%羧甲基纤维素钠为助溶剂)100 mg/kg,5 h后取股静脉血.提取抗凝全血中的DNA,采用琼脂糖凝胶电泳确认DNA的提取效果.将提取的DNA在 0.1 nmol/L HCl、90 ℃恒温水浴箱中酸水解4 h,乙酸乙酯提取酸水解产物--四醇-苯并(a)芘.高效液相色谱法检测,最后用高效液相色谱-质谱法确认.结果 BaP 染毒组与溶剂对照组和阴性对照组比较,高效液相色谱检测有新的色谱峰产生,质谱确定其相对分子质量与四醇-苯并(a)芘一致.结论 本实验的染毒方法能使大鼠产生 BPDE-DNA 加合物;建立的高效液相色谱法可以血液为样品检测 BPDE-DNA 加合物.

The Formation of BPDE-DNA Adduct in Rat and Its Determination by High Performance Liquid Chromatography

OBJECTIVE: To study the benzo (a) pyrene (BaP) induced DNA adduct in rat and establish a method to measure the DNA adduct in blood by high performance liquid chromatography (HPLC). METHODS: The SD rats were treated with 100 mg/kg of BaP-DMSO (cosolvent: 1% sodium carboxymethyl cellulose) once by i.p., and the blood of femoral vein was collected 5 hours later. The blood DNA was extracted by kit and confirmed by agarose gel electrophoresis. After extraction, the DNA adducts were hydrolyzed in 0.1 nmol/L HCl at 90 degrees C for 4 hours. The acid-hydrolysis products (BP-tetrols) of DNA adducts were extracted by ethyl acetate and measured by HPLC, and finally confirmed by HPLC-MS. RESULTS: In chromatogram there were new peaks to occur for rats treated by BaP, with compared to control. By HPLC-MS, one of the new peaks was confirmed to be BP-tetrol. CONCLUSION: The rats ingesting BaP in the way described in this experiment can form DNA adducts, and the adducts in blood can be detected by HPLC.