神经管畸形小鼠胚胎神经上皮细胞的黏弹性特性

Viscoelastic properties of embryonic neuroepithelial cells in neural tube defects mice

目的探索胚胎神经上皮细胞力学特性与神经管闭合之间的关系。方法用全反式维甲酸对胚胎发育第7．5天的小鼠进行灌胃处理，制备小鼠神经管畸形（NTDs）模型。分别于胚胎发育第9．5天与11．5天处死孕鼠，提取正常及神经管畸形原代神经上皮细胞，采用微管吸吮技术结合标准固体黏弹性力学模型分析神经上皮细胞的力学特性。结果小鼠胚胎神经上皮细胞力学特征表现为典型的黏弹性固体特征。与对照组比较，NTDs组的神经上皮细胞的3个黏弹性参数（平衡模量、瞬态模量和表观黏性系数）均明显升高，差异有统计学意义（均P〈0．05），但同一组细胞的黏弹性参数在不同时间点的差异无统计学意义（均P〉0．05）。结论胚胎神经上皮细胞变形能力下降可能是神经管闭合障碍产生的因素之一。

Objective To explore the role of mechanical properties of embryonic neuroepithelial ceils in the process of neural tube closure. Methods Neural tube defects （NTDs） mouse model was established by intragastrie administration with all-trans retinoic acid at embryo 7.25 day. All the pregnant mice were sacrificed at embryo 9.5 day and 11.5 day, respectively, and the primary neuroepithelial cells were isolated from neural tube tissue of normal and NTDs mice, respectively. The mechanical characteristics of neuroepithelial cells were analyzed using mieropipette aspiration technique combined with a standard solid viscoelastic mechanical model. Results The mechanical characteristics of mouse embryonic neuroepithelial cells showed typical viscoelastic solid characteristics. Compared with the control group, the three viscoelastic parameters, i.e. equilibrium modulus, transient modulus and apparent viscosity coefficient, of the neuroepithelial cells in the NTDs group were significantly increased, and the differences were statistically significant （all P〈0.05）. However, there was no significant difference in the viscoelastic parameters of the same group between embryo 9.5 d and 11.5 d （all P〉0.05）. Conclusion The decrease in the deformability of embryonic neuroepithelial cells may be one of the factors responsihle for neural tube closure disorders.