Liping Wang, Boqi Li, Qi Wang, Xiaomin Tie, Yishan Liu
Dept. of Pediatric Dentistry and Preventive Dentistry, The First Affiliated Hospital of Xinjiang Medical University, Urumqi 830000, China.
Hua Xi Kou Qiang Yi Xue Za Zhi. 2016 Aug 1;34(4):341-345. doi: 10.7518/hxkq.2016.04.004.
To observe the expression of wingless-type MMTV integration site family, member 5A (Wnt5A)/receptor tyrosine kinase-like orphan receptor 2 (Ror2) signal in the dental follicle cells during the normal eruption of the teeth as well as to explore the relationship between the expression of dental follicle cells and the formation of mature osteoclasts and eruption of the teeth.
The mandibulars of 1-13 d old SD rats were separated to observe the growth and develop-ment of the teeth and alveolar bone through hematoxylin-eosin(HE) staining. Ror2 and Wnt5A expressions in rat dental follicle were also observed through immunohistochemistry. Dental follicle cells from the lower first intact molar germs of 5-6-day old SD rats were separated and cultured.
On the second day after birth, the dental follicle began to differentiate into periodontal tissues, but no obvious changes were observed in the alveolar bone one to three days after birth. On the fourth day, the number of osteoclasts increased significantly. The results of immunohistochemistry showed that Wnt5A was not significantly expressed in rat dental follicle tissues before the fourth day, but positive expression was expressed in the next day and continued to express to thirteenth days. Ror2 was expressed in the rat dental follicle at postnatal days 1-3, but weak expression was found in days 4-13.
Wnt5A and Ror2 expressions in the process of tooth eruption have specific time distributions, suggesting that these expressions may participate in the regulation of the eruption of the teeth.
观察无翅型MMTV整合位点家族成员5A（Wnt5A）/受体酪氨酸激酶样孤儿受体2（Ror2）信号在牙齿正常萌出过程中牙囊细胞中的表达，探讨牙囊细胞表达与成熟破骨细胞形成及牙齿萌出之间的关系。
分离113日龄SD大鼠的下颌骨，通过苏木精-伊红（HE）染色观察牙齿及牙槽骨的生长发育情况。采用免疫组织化学法观察大鼠牙囊中Ror2和Wnt5A的表达情况。分离并培养56日龄SD大鼠下颌第一恒磨牙完整牙胚的牙囊细胞。
出生后第2天，牙囊开始分化为牙周组织，但出生后13天牙槽骨未见明显变化。第4天，破骨细胞数量显著增加。免疫组织化学结果显示，Wnt5A在第4天前大鼠牙囊组织中表达不明显，第5天开始呈阳性表达，并持续至第13天。Ror2在出生后13天在大鼠牙囊中表达，第4~13天表达较弱。
Wnt5A和Ror2在牙齿萌出过程中的表达具有特定的时间分布，提示这些表达可能参与牙齿萌出的调控。
