Role of Prostaglandins on Resorption of Deciduous Teeth during Teeth Exchange in Rabbits

前列腺素对家兔换牙过程中乳牙吸收的作用

• 批准号: 06672057
• 负责人: ARITA Kenji
• 金额: $ 1.34万
• 依托单位: The University of Tokushima
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06672057/
• 关键词: Tooth exchang; Root resorption; Root-resorbing tissure; Prostagrandin; Indomethacin; Rabbit; 乳歯; RIA; 破歯細胞; 動物実験

The study aimed to confirm whether PGE2 had any connection with physiological root resorption. My previous study showed that resorption of deciduous upper incisors in rabbits started on the 9th day postnatally and that the resorption occured in 3 stages : (1) early stage (9-13 days), where there was active resorption by odontclasts ; (2) resting stage (15-21 days) ; and (3) final stage (23-25 days), where resorption reoccured by odontclasts and inflammatory ceels. For this study, 64 young rabbits used. The control groups were injected with normal salin, and the treatment groups were injected with 10.0 mg/kg indomethacin at 9hr and 3hr before sacrifice. The maxillae were excised, and the root-resorbing tissue (RRT) were carefully removed and the PGE2 level of them were measured by RIA using [^<125>I] PGE2-RIA kit at 5,9,13,17,21 and 25 days, respectively. Additionally, the level of PGE2 of the oral mucosa of hard palate (OMP). The resuls were as follows :The concentration of PGE2 (mean<plus-minus>S.D.pg/mg wet.tiss.) of RRT in control groups were 446<plus-minus>419 at 5 days, 3751<plus-minus>2454 at 9 days, 748<plus-minus>504 at 13 days, 180<plus-minus>19 at 17 days, 253<plus-minus>128 at 21 days and 1520<plus-minus>398 at 25 days, and those of OMP in control groups were 87<plus-minus>98 at 5 days, 242<plus-minus>377 at 9 days, 25<plus-minus>18 at 13 days, 60<plus-minus>47 at 17 days, 362<plus-minus>131 at 21 days and 1168<plus-minus>1164 at 25 days, respectively. PGE2 levels at 9,13 and 25 days were greater than at 5,17 and 21 days in control groups (p<0.05). PGE2 in RRT was higher at 9 and 13 days than in OMP (p<0.05). Except at 5 days, PGE2 in treatment group was always lower than in control group, in both RRT and OMP (p<0.05). These results strongly suggest that PGE2 can possibly act as a chemical mediator of odontoclasic root resorption occurr

本研究旨在证实PGE 2是否与生理性牙根吸收有关。本实验室以前的研究表明，兔乳上切牙在出生后第9天开始吸收，吸收分三个阶段：（1）早期（2）静止期（9-13天），破牙体吸收活跃;（3）晚期（23-25天），破牙细胞和炎性细胞再吸收。本研究使用了64只幼兔。对照组注射生理盐水，治疗组于处死前9 h和3 h注射吲哚美辛10.0 mg/kg。分别<125>于术后5、9、13、17、21、25 d取上颌骨，用放射免疫法测定牙根吸收组织（RRT）中PGE 2的含量。同时测定硬腭口腔粘膜（oral mucosal of hard palate，OMP）中前列腺素E_2（PGE_2）的含量。结果表明：前列腺素E_2（平均<plus-minus>S. D. pg/mg湿组织）浓度与对照组相比，差异有统计学意义（P &lt; 0.05）。对照组的RRT分别为<plus-minus>5天446 419、<plus-minus>9天3751 2454、<plus-minus>13天748 504、<plus-minus>17天180 19、<plus-minus>21天253 128和25<plus-minus>天1520 398，对照组的OMP分别为<plus-minus>5天87 98、<plus-minus>9天242 377、<plus-minus>13天25 18、<plus-minus>17天60 47、<plus-minus>21天362 131和<plus-minus>25天1168 1164。对照组第9、13和25天的PGE 2水平高于第5、17和21天（p&lt;0.05）。RRT组第9天和第13天的PGE 2高于OMP组（p&lt;0.05）。除第5天外，治疗组在RRT和OMP中的PGE_2均低于对照组（p&lt;0.05）。提示PGE_2可能是破牙性牙根吸收发生的化学介质。