The disribution of ganglioside sialidase on developing mouse tooth germ

神经节苷脂唾液酸酶在小鼠牙胚发育中的分布

• 批准号: 13671892
• 负责人: AKITA Hirotoshi
• 金额: $ 1.79万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13671892/
• 关键词: ganglioside sialidase; tooth germ; transgenic mouse; immunocytochemistry; histology; tissue fixation; 歯胚上皮; 免疫組織化学; 透過型電子顕微鏡; 歯胚・上皮

Ganglioside sialidase is one type of the animal sialidases, whose activity is innately localized on cell membrane by biological definition. This project aimed at confirming the morphological localization and biological role of this enzyme. An immunocytochemical study proved the enzyme being localized on cell membrane of COS cells transfected with bovine cDNA of the enzyme, and of skeletal muscle cells in transgenic mice expressed with the human cDNA. To elucidate a biological role of the enzyme, a histological study was done in incisors of abovementioned transgenic mice. Mouse incisors continue to grow during the animal life. Therefore we can study an effect of some experimental condition on tooth formation at any time of the animal life. The histological changes of the enamel organ and tooth were ambiguous in the transgenic mice because of inadequate tissue fixation with paraformaldehyde. To get good histological features, the tissue fixation method needed to be improved. Mice under anesthetization were fixed with the chemical fixative which was infused into the left ventricle through a catheter by using a peristaltic pump. The fixative circulating the body along blood vessels was drained from the right atrium cut open. The shorter surgical operation time to insert a catheter into the left. ventricle you will take, the better histological features you will get. A catheter was devised for shortening the surgical operation time. The best catheter was a polyethylene tubing 0.9mm in diameter connected to a metal needle (26 gauge) at the one end. The left ventricle was punctured by the needle after thoracotomy. To hold the needle in place the heart and needle were glued by using Aron Alpha A (Toagosei Co., Ltd.), one of surgical glues. Taking much time for improving the tissue fixation method, the histological study has not yet been completed.

神经节苷脂唾液酸酶是动物唾液酸酶的一种，根据生物学定义，其活性固有地定位于细胞膜上。该项目旨在确认该酶的形态定位和生物学作用。免疫细胞化学研究证明，该酶定位于用该酶的牛cDNA转染的COS细胞的细胞膜上，以及用人cDNA表达的转基因小鼠的骨骼肌细胞的细胞膜上。为了阐明该酶的生物学作用，对上述转基因小鼠的门牙进行了组织学研究。小鼠的门牙在动物一生中不断生长。因此，我们可以研究某些实验条件对动物生命中任何时间牙齿形成的影响。由于多聚甲醛组织固定不充分，转基因小鼠牙釉质器官和牙齿的组织学变化不明确。为了获得良好的组织学特征，需要改进组织固定方法。将麻醉下的小鼠用化学固定剂固定，并使用蠕动泵通过导管注入左心室。沿着血管循环体内的固定剂从切开的右心房排出。将导管插入左侧的手术时间较短。您将获取的心室，您将获得更好的组织学特征。设计了导管以缩短手术时间。最好的导管是直径 0.9 毫米的聚乙烯管，其一端连接到金属针（26 号）。开胸手术后，左心室被针刺穿。为了将针固定到位，使用 Aron Alpha A（Toagosei Co., Ltd.）（一种外科胶水）将心脏和针粘合在一起。组织固定方法的改进需要很长时间，组织学研究尚未完成。