基于4%中性甲醛固定肝组织的大鼠肝微核实验方法的建立与验证  

Establishment and validation of liver micronucleus assay in rats using 4%neutral formaldehyde-fixed tissues

作　　者：赵田田 何伟伟 周长慧 赵泽浩 杨紫轩 常艳 ZHAO Tiantian;HE Weiwei;ZHOU Changhui;ZHAO Zehao;YANG Zixuan;CHANG Yan(China State Institute of Pharmaceutical Industry,Shanghai Innostar Bio-tech Co.,Ltd,Shanghai 201203,China)

机构地区：[1]中国医药工业研究总院上海益诺思生物技术股份有限公司,上海201203

出　　处：《中国药理学与毒理学杂志》2024年第6期436-444,共9页Chinese Journal of Pharmacology and Toxicology

基　　金：上海市科委研发平台专项(21DZ2291000)。

摘　　要：目的建立并验证基于4%中性甲醛固定肝组织制备肝细胞的大鼠肝微核实验(LMNT)方法(甲醛固定-LMNT法)。方法(1)SD大鼠分为雌性和雄性组,然后分别随机分为溶剂对照组和肝微核阳性化合物N-亚硝基二乙胺(DEN)12.5 mg·kg^(-1)组,每组5只,分别ig给予生理盐水和DEN,每天1次,连续14 d后取肝组织,同时用胶原酶消化-LMNT法和甲醛固定-LMNT法检测微核化肝细胞数量和处于有丝分裂期肝细胞数,分别计算肝细胞微核率和有丝分裂指数,肝细胞微核率>0.07%判定为阳性结果。(2)雄性SD大鼠分为喹啉(30,60和120 mg·kg^(-1))组、N-亚硝基吡咯烷(NPYR,25,50和100 mg·kg^(-1))组、各自溶剂对照组(NPYR,去离子水;喹啉,玉米油)及阳性对照DEN(12.5 mg·kg^(-1))组,每组5~6只,连续ig 15 d。每日记录体重,实验结束取肝记录肝总重,计算肝系数。自动生化分析仪检测肝功能相关血清生化指标谷丙转氨酶(GPT)、谷草转氨酶(GOT)活性和血清总胆红素(T-BIL)、直接胆红素(D-BIL)的水平。采用胶原酶消化-LMNT法和甲醛固定-LMNT法测定肝细胞微核率,用外周血微核实验和肝彗星实验评价喹啉和NPYR遗传毒性。结果(1)与各自溶剂对照组的肝细胞微核率(0.069%和0.030%)相比,甲醛固定-LMNT法测得的DEN组雄性大鼠肝细胞微核率为1.10%,雌性大鼠为0.82%,均显著升高(P<0.05);与各自溶剂对照组(0.060%和0.030%)相比,胶原酶消化法-LMNT法测得的DEN组雄性大鼠肝细胞微核率为1.45%,雌性大鼠为0.46%,均显著升高(P<0.05),判定为阳性。2种方法中雄性大鼠的肝细胞微核率均显著高于雌性(P<0.05)。与各自溶剂对照组相比,2种方法测得的DEN组雄性和雌性大鼠肝细胞有丝分裂指数均无明显差异。(2)与溶剂对照组相比,NPYR 50和100 mg·kg^(-1)组大鼠体重在ig第7~14天显著降低(P<0.01),DEN组在ig第8~14天显著降低(P<0.01);喹啉120 mg·kg^(-1)组大鼠在ig第4~14天显著降低(P<0.01),DEN组在ig第10~OBJECTIVE To establish and validate a rat liver micronucleus test(LMNT)method based on fixation of liver tissue with 4%neutral formaldehyde(HCHO fixation)for preparation of hepa-tocytes(HEPs).METHODS①The LMNT based on neutral HCHO fixation(HCHO fixation-LMNT)was established using the liver micronucleus positive compound N-nitrosodiethylamine(DEN).SD rats were divided into female and male groups,and each group was randomly subdivided into the vehicle control group and DEN 12.5 mg·kg^(-1) group,with five rats in each.The rats were ig administered with normal saline and DEN once a day for 14 consecutive days,after which liver tissues were collected.Some of the tissue was digested with collagenase to prepare HEP suspension,and the remaining tissue was used to prepare HEP suspension with HCHO fixation.After staining with SYBR Gold,the number of micronucleated hepatocytes(MN-HEP)and the number of HEPs in the mitotic phase were counted under a microscope.The micronucleus rate of HEP(MN-HEP rate)and the mitotic index were calculated,and an MN-HEP rate>0.07%was considered positive.②Male SD rats were divided into the quinoline(30,60,120 mg·kg^(-1))group,N-nitrosoopyrrolidine(NPYR,25,50,100 mg·kg^(-1))group,vehicle control group(deionized water for NPYR,and corn oil for quinoline),and positive control DEN(12.5 mg·kg^(-1))group,with 5-6 rats per group,and were ig administrated for 15 consecutive days.Body mass was recorded daily,and at the end of the experiment,the liver was removed to record the total liver weight,and calculate the liver coefficient.Liver function-related serum biochemical indicators including glutamic-pyruvic transaminase(GPT),glutamic-oxaloacetic transaminase(GOT)activities,and levels of total bili-rubin(T-BIL)were measured and direct bilirubin(D-BIL)using an automatic biochemical analyzer.The MN-HEP rate was determined using the collagenase digestion and HCHO fixation methods,and the peripheral blood MN assay and hepatocellular carcinoma comet assay were conducted to evaluate the genotoxicity of

关 键 词：肝微核实验 甲醛固定 胶原酶消化 

分 类 号：R99[医药卫生—毒理学]