Iida Sachiyo, Hara Tetsuya, Araki Daisuke, Ishimine-Kuroda Chisa, Kurozumi Akimasa, Sakamoto Shunichi, Miyazaki Takako, Minagi Shogo
Department of Occlusal and Oral Functional Rehabilitation, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8525, Japan.
Department of Occlusal and Oral Functional Rehabilitation, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8525, Japan.
Arch Oral Biol. 2014 Feb;59(2):133-41. doi: 10.1016/j.archoralbio.2013.10.003. Epub 2013 Oct 29.
The present study aimed to identify the effect of memory-related genes on male rats tested for spatial memory with either molar teeth extraction or its restoration by occlusal support using experimental dentures.
Memory-related genes were detected from hippocampi of male Wistar rats (exposed to teeth extraction with or without dentures, or no extraction (control)) (7-week old) after behavioural testing (via the radial maze task) using a DNA microarray. The time course of the expression of these genes was evaluated by quantitative real-time polymerase chain reaction (PCR) (on 49-week-old rats).
In preliminary experiments, to determine which memory genes are affected by spatial memory training, DNA microarray analysis revealed that thyrotropin-releasing hormone (Trh) and tenascin XA (Tnxa) were up-regulated and neuronatin (Nnat) and S100a9 were down-regulated after the maze training. The expression of Tnxa, Nnat and S100a9 of 49-week-old rats (during the time course) via quantitative real-time PCR was consistent with the results of microarrays of the preliminary experiment. Expression of Trh that was evaluated by quantitative real-time PCR did not agree with the results for this gene from the microarray for all groups. Therefore, expression of Trh may have increased in only young, trained rats. The expression of S100a9 prior to the maze task was down-regulated in only the extraction group.
These results demonstrated that Trh, Tnxa and Nnat genes were affected according to the degree of memory in male rats. This study also indicated that S100a9 is a memory-related gene, which is affected by the presence of occlusal support.
本研究旨在确定记忆相关基因对雄性大鼠空间记忆的影响，这些雄性大鼠通过磨牙拔除或使用实验性义齿进行咬合支持修复来测试空间记忆。
在行为测试（通过放射状迷宫任务）后，使用DNA微阵列从雄性Wistar大鼠（7周龄，暴露于拔牙或不拔牙（对照组），有或无义齿）的海马中检测记忆相关基因。通过定量实时聚合酶链反应（PCR）（对49周龄大鼠）评估这些基因表达的时间进程。
在初步实验中，为了确定哪些记忆基因受空间记忆训练影响，DNA微阵列分析显示，迷宫训练后促甲状腺激素释放激素（Trh）和腱生蛋白XA（Tnxa）上调，神经生长抑制素（Nnat）和S100a9下调。通过定量实时PCR对49周龄大鼠（在时间进程中）的Tnxa、Nnat和S100a9表达与初步实验的微阵列结果一致。通过定量实时PCR评估的Trh表达与所有组微阵列中该基因的结果不一致。因此，Trh的表达可能仅在年轻的训练大鼠中增加。仅在拔牙组中，迷宫任务前S100a9的表达下调。
这些结果表明，Trh、Tnxa和Nnat基因根据雄性大鼠的记忆程度受到影响。本研究还表明，S100a9是一个与记忆相关的基因，受咬合支持的存在影响。
