Development of a rat model for studying the behavioral assessment of dysphagia

• Project/Area Number: 16K11589
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Prosthodontics/ Dental materials science and
• Research Institution: Niigata University
• Principal Investigator: Naru Shiraishi 新潟大学, 医歯学系, 助教 (60585355)
• Co-Investigator(Kenkyū-buntansha): 井上 誠 新潟大学, 医歯学系, 教授 (00303131) ; 辻村 恭憲 新潟大学, 医歯学系, 准教授 (00548935) ; 佐々木 啓一 東北大学, 歯学研究科, 教授 (30178644)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2018: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2017: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2016: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 摂食嚥下 / 覚醒動物 / 咀嚼 / 覚醒行動下 / 嚥下 / 慢性実験 / 咀嚼障害 / インプラント / マルチレコーディング / 大脳皮質 / ニューロンレコーディング / 大脳皮質咀嚼野

Outline of Final Research Achievements

We have optimized tooth extraction and implant procedures and established protocols for high-speed biplanar videofluoroscopy (XROMM) imaging and analysis of mandible and tongue markers to permit objective assessment of feeding kinematics over time in freely behaving rats before and after dental manipulations. Rats were chronically implanted with radiopaque beads into the skull, mandible, and tongue to characterize kinematics of feeding behaviors using XROMM. In addition, We have successfully developed a series of surgical procedures and the protocol to obtain the natural feeding behavior in rats. The bipolar polyurethane-coated stainless steel wire electrodes were placed in the bilateral masseter, right suprahyoid and right thyrohyoid muscles for electromyogram (EMG) recording.
These protocols are extremely meaningful to assess the behavioral changes of jaw and tongue kinematics , and to analyze the effects on mastication and swallowing during natural feeding and for dysphagia.

Academic Significance and Societal Importance of the Research Achievements

本研究は，咀嚼や嚥下時の口腔機能がもたらす大脳皮質をはじめとした上位脳への効果を解明することを目的とし，高齢者の咀嚼・嚥下機能維持・改善のための歯科治療の重要性を明らかにすることであった．第一に，覚醒動物（麻酔で眠っていない動物）での摂食運動の記録方法の確立を目指し，レントゲンを用いた３次元的計測ならびに筋電図による咀嚼や嚥下時の筋活動記録を選択した．自由行動では，嚥下のタイミングは咀嚼運動には影響を与えないこと，さらに歯の喪失に伴う口腔機能や咀嚼機能の低下は咀嚼のみに影響を与えるわけではなく，嚥下時の顎運動サイクルの延長を認め，嚥下動作にも影響を与えることが考えられた．

Research Products

• [Int'l Joint Research] シカゴ大学(米国)
• [Int'l Joint Research] シカゴ大学(米国)
• [Presentation] Development of a rat model for studying the behavioral assessment of dysphagia. (2019)
  • Author(s): Naru Shiraishi, Kouta Nagoya, Takanori Tsujimura, Makoto Inoue
  • Organizer: Dysphagia Research Society (DRS) 27th Annual Meeting
  • Int'l Joint Research
• [Presentation] Development of a rat model for studying the relationship between oral environmental changes and alterations in mastication/swallowing patterns. (2017)
  • Author(s): Shiraishi N, Avivi-Arber L, Lever T, Inoue M, Ross C, Takahashi K
  • Organizer: 25th Anniversary Annual Meeting Dysphagia Research Society
  • Place of Presentation: Portland, US
  • Year and Date: 2017-03-02
  • Int'l Joint Research
• [Presentation] Development of semi-automatic procedure for detection and tracking of fiducial markers for orofacial kinematics during natural feeding. (2017)
  • Author(s): Bunyak F, Shiraishi N, Palaniappan K, Lever T, Avivi-Arber L, Takahashi K
  • Organizer: The 39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society
  • Int'l Joint Research
• [Presentation] Analysis of the relationship between oral environmental changes and alternations in mastication/swallowing patterns of rats using 3D videofluoroscopic technique. (2017)
  • Author(s): Shiraishi N, Avivi-Arber L, Zimerman A, Kataria N, Lever T, Inoue M, Ross C, Takahashi K
  • Organizer: 7th ESSD Congress
  • Int'l Joint Research