先天性马蹄内翻足动物模型胚胎后肢（芽）评分系统的建立

Scoring system of hind-limb development in a murine model

目的建立一套稳定的评分系统，提供客观的观察指标来确认胚胎早期先天性马蹄内翻足（congenital clubfoot，CCF），进行序列胚胎研究。方法60只Wistar大白鼠，体重220250g，随机分成实验组和对照组各6组。从怀孕第10天起，将维甲酸玉米油混悬液经胃管单次注入，以建立马蹄内翻足动物模型，分别在受孕第13、14、15、16、17、18天取出胎鼠的后肢芽并经过一系列处理。应用评分系统对胎鼠进行评分。结果经评分系统得出的动物模型CCF发病率为80．9％，经评分系统矫正后的CCF发病率较既往报道高。在实验组和对照组之间的软骨分化存在显著差异。结论应用评分系统可以有效地筛选出CCF，可以对筛选出的CCF胚胎在关键的研究时间窗口进行系列研究，有效地解决了长期困扰CCF研究难以深入的瓶颈问题。

Objective Quantification of the severity of congenital clubfoot is essential for its research and treatment. Up to date, no scoring system is available for hind limb bud development. In this study,a scoring system was established based on a murine model. Methods Sixty female Wistar rats weighing 220-250 g were randomized into the six control groups and six experimental groups. Vaginal sperm plug detection day was considered to be day 0 of gestation. Hind limb buds from fetuses of E13, 14,15,16,17 and 18 days were removed and processed. Results Morphogenetic differentiation changes were detected in the experimental groups. According the new scoring system, clubfoot-like deformity was present in 80. 9% of the experimental fetuses. We were able to quantify the extent morphogenetic differentiation of the hind limb accordingly. Conclusions Congenital clubfoot deformities begin at early developmental stage and become exaggerated as the fetuses mature. The scoring system can quantify the extent of congenital clubfoot deformity and facilitate its management.