目的 观察和分析Nonmuscle Myosin II（NM II）家族基因在斑马鱼胚胎期咽弓的表达及其对咽弓发育的影响。方法 通过斑马鱼胚胎整体原位杂交及冰冻切片技术（n=10），观察NM II家族基因在斑马鱼胚胎期咽弓的表达情况。利用软骨的阿辛蓝染色方法，对野生型对照组（n=10）和Blebbistatin处理组（每个浓度n=10）的斑马鱼胚胎进行比较，分析NM II对斑马鱼胚胎期咽弓发育和形成的影响。结果 胚胎发育72 hours post-fertilization（hpf），NM II-B在斑马鱼发育着的咽弓部位有特异性的表达；120 hpf，NM II-B在咽弓表达增加。Blebbistatin特异性抑制NM II-B功能后，斑马鱼咽弓发生明显发育缺陷，部分软骨细胞出现显著形态改变；抑制咽弓形成的作用与Blebbistatin浓度呈现剂量依赖效应。结论 NM II-B通过影响咽弓软骨细胞从而调节斑马鱼胚胎期咽弓的发育。

Objective To analyze the expression of Nonmuscle Myosin II (NM II) in pharyngeal arches and the function of NM II on the development of pharyngeal arches in zebrafish embryos. Methods The expression of NM II-B in pharyngeal arches in zebrafish embryos was observed by whole-mount in situ hybridization and cryostat section (n=10). The function of NM II-B on the development of pharyngeal arches in zebrafish embryos was analyzed following the comparison of wild type (n=10) and Blebbistatin-treated (n=10 per concentration) zebrafish embryos by cartilage Alcian blue staining. Results The expression of NM II-B in pharyngeal arches in zebrafish was detected at 72 hours post-fertilization (hpf); the expression of NM II-B in pharyngeal arches increased at 120 hpf. The pharyngeal arches in zebrafish appeared obvious developmental defects, and a few of chondrocytes showed significant morphological changes after Blebbistatin inhibition of NM II-B functions, which was at a dose-dependent manner. Conclusion NM II-B regulates the development of pharyngeal arches through affecting the chondrocytes of pharyngeal arches in zebrafish embryos.