钟状期小鼠磨牙牙胚组织中蛋白聚糖类型的检测分析

Proteoglycans in the Bell Stage of Odontogenesis in Mouse Molars:An in vitro Study

目的:检测分析钟状期小鼠磨牙牙胚组织中蛋白聚糖的类型。方法:建立钟状期小鼠磨牙牙胚体外培养模型,用核素标记,凝胶层析,碱处理及酶消化的方法分析体外培的养牙胚组织中蛋白聚糖的类型。结果:体外培养的小鼠钟状期磨牙牙胚、成釉器与牙乳头中[35S]标记的大分子经Superose 6层析柱层析后,均得到3个洗脱峰。其中第1个洗脱峰经硫酸软骨素酶ABC消化后完全消失,第2、第3个洗脱峰在硫酸软骨素酶ABC消化后峰值降低,继续用乙酰肝素酶消化后则基本消失。只用硫酸角质素酶处理,上述3个洗脱峰均未发生改变。碱处理后3个洗脱峰均消失,并在有效分配系数Kd=0.47处出现1个新的洗脱峰。结论:小鼠钟状期磨牙牙胚、成釉器与牙乳头组织含有大分子硫酸软骨素蛋白聚糖、小分子硫酸软骨素蛋白聚糖以及硫酸乙酰肝素类蛋白聚糖,但不存在硫酸角质素蛋白聚糖。

Objective： To investigate the expression and synthesis of proteoglycans in the bell stage of odontogenesis in cultured mouse molars. Methods： Mouse molar tooth germs were obtained from 30 pregnant ICR mouse and to establish culture model in vitro by Trowell culture system at early bell stage. Enamel organs and dental papilla were separated. and metabolically labeled with [^35S]Na2SO4 as precursors. The culture suspension was analyzed by gel chromatography, enzymatic digestion, and alkaline treatment. Results： Three eluted peaks were obtained in all samples. A major peak eluted at Vo （Vo peak） which was completely susceptible to digestion with chondroitinase ABC. The other two were susceptible to digestion with chondroitinase ABC and Heparitinase respectively. After alkaline borohydride reaction, the eluted three peaks disappeared and a large peak was observed at effective distribution coefficient Kd=0.47. However, all [^35S]-labeled samples were not susceptible to digestion with keratanase. Conclusion： At the bell stage of odontogenesis, a macromolecule chondroitin sulfate proteoglycan, micromolecule ehondroitin sulfate proteoglycans, and heparan sulphate proteoglycans were identified. No kerantin sulfate was detected.