BrdU体内标记腺样囊性癌肺转移灶的实验观察

EXPERIMENTAL STUDY OF BRDU LABEL IN VIVO IN MATASTATIC LUNG CARCINOMA FROM ACC-M

目的 动态观察非放射性标记物 Brd U在动物体内标记情况 ,为 Brd U取代 3H- Td R提供依据。方法 6只裸鼠经尾静脉分别注入 Acc- M细胞 1× 10 6 / 0 .2 m l,4周后腹腔注射 Brd U2 0 0 μg/ g体重 ,注射 0 .5 h～ 2 0 h期间分别取材固定 ,免疫组化 ABC法染色 ,统计标记指数。结果 所有裸鼠形成肺转移癌阳性细胞核标记指数 (L I)约2 0 %～ 40 %。单次注射 Brd U后 ,L I不随注射时间延长而增加。正常组织中 ,肝窦和肠绒膜上皮有标记阳性细胞 ,肾、胰、脾等器官未见。结论 Brd U体内标记法可替代 3H- Td R应用于细胞增殖研究 ,避免放射性污染 ,但在人体内标记 ,尚需进一步探索。

Objective To observe continuously the result of incorporation with BrdU in vivo, so that tritiated thymidine can be replaced.Methods Six BALB/c nude mice were injected Acc-M cells of 1×10 6/0.2ml into their tail vein respectively. Four weeks later, BrdU with 200μg/g of body weight was injected via abdominal cavity of mice. Then, killed the animals after injecting BrdU 0.5hour, 1hour, 2hours, 4hours, 16hours, and 20hours respectively. We gained different organs from these mice, which included lungs, liver, pancreas, spleen, kidneys, and so on. These specimens were normally treated with method of immunohistochemical ABC. One thousand cells or so were observed in each slice, and the number of the positive cells was counted. Label index (LI)=positive cells/all cells observed X 100%.Results There were metastatic lung carcinomas in all six mice. Voluminous lungs with some greyish white nodes on the surface. The positive cells showed tawny color under a microscopy. Those label indexes of BrdU were 20%~40% or so and the LI didn't increase in number with longer incorporative time after injecting BrdU only one time. In normal tissues, positive staining was in those cells around hepatic sinus and intestinal epithelial cells, and negative staining was those of kidneys, pancreata, and spleens. Conclusion Bromodeoxyuridine is a thymidine analogue of DNA precursor. It can competitively incorporate into single strain DNA nucleotide sequences to replace the thymidine. The method of BrdU label in vivo can substitute for tritiated thymidine in research on cell proliferation, which avoid radioactive pollution. BrdU label is a sensitive, convenient, rapid, and non-radioactive method of incorporating into DNA. It has a wide prospect and lots of practical value, but it also need a longer period and deeper researches.