氯乙烯对胚胎神经管发育致畸作用的研究-第三军医大学学报.doc

氯乙烯诱导小鼠胚胎神经管发育畸形的研究 何 乐1，杨君杰1，彭玉立1，王景鹏1，秦茂林2 ，李红丽2 *（1第三军医大学学员旅七队， 2第三军医大基础部组胚教研室，发育生物学教研室，重庆市神经科学研究所，重庆 400038）：观察孕早期不同剂量氯乙烯（VC）染毒后胎鼠神经系统发育以及神经上皮细胞增殖和凋亡的变化情况，明确VC对神经系统发育的致畸作用。方法 将孕鼠随机分为实验组和对照组，实验组分别用不同剂量的VC对孕6.5d的小鼠进行腹腔染毒，对照组注射花生油。均于E12.5d取胚胎。观察胎鼠的表观发育情况，计算胚胎畸形率以及神经系统异常的发生率。运用PCNA免疫组织化学技术和TUNEL染色技术检测并观察神经管上皮细胞的增殖及其凋亡的变化。结果 （1）中剂量VC组胎鼠活胎率下降，活胎中畸胎发生率高达51％，其中神经管畸形发生率占40％，与正常对照组相比有显著差异（P0.05）；高剂量VC组胎鼠活胎率仅占55％，活胎中畸胎率明显增高占71％，其中神经管畸形发生率占50％，与正常对照组相比差异显著（P0.05）。（2）中剂量和高剂量VC组胚胎神经管上皮厚薄不一致；高剂量组神经管多数呈明显未闭合状，神经管周围的间充质细胞肿胀，轮廓不清。（3）正常小鼠神经管神经上皮内可见PCNA阳性细胞与TUNEL阳性细胞分布；实验组各型阳性细胞分布与对照组相似，但随着染毒剂量的增加，PCNA阳性细胞表达减少，而TUNEL阳性细胞表达增多。结论 孕早期剂量氯乙烯染毒可导致胚胎畸形率升高，神经管畸形比率也相应上升。氯乙烯主要可抑制神经上皮细胞的增殖、诱导细胞凋亡发生增多，导致增殖与凋亡比例失调。 关键词：氯乙烯神经管畸形PCNA、TUNELhe Experimental study on mouse embryos neural tube defect induced by vinyl chloride HE Le1, YANG Jun-jie1, PENG Yu-li1, WANG Jing-peng1, QIN Mao-ling2, LI Hong-li2 * (17th student team; 2 Department of Histology and Embryology, Department of Developmental Biology, Institute of Neuroscience, The Third Military Medical University, Chongqing 400038, China; Abstract: Objective: Observe the development and diversity of mouse embryo’s nervous system, proliferation and apoptosis of the neuroepithelial cell , to indentify the influence of different dose of vinyl chloride（VC）on the development of neural tube in , and to further explore the mechanism that causes the neural tube defect (NTD).Methods: Divide the pregnant mice into the experimental group(EG) and the control group(CG) randomly .The EG was used narcotics by different doses of VC in E6.5 , meanwhile , the CG was injected by arachis oil .Both of the groups were dissected in E12.5 , immobilized by 4% PFA , paraffin-embedded and cut continuously. The expression of PCNA in the development of neural tube was detected by immunohistochemical labeling technology. Using the TUNEL staining, observe the apoptosis in the development of neural tube. Results: (1) The living embryo in the EG of middle dose decreased, in whic