Neural mechanisms of trigeminal rhythmical activities

1999 Fiscal Year Final Research Report Summary

• Project/Area Number: 10307050
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Surgical dentistry
• Research Institution: Osaka University
• Principal Investigator: MATSUYA Tokuzo Faculty of Dentistry, Osaka University Professor, 歯学部, 教授 (40028759)
• Co-Investigator(Kenkyū-buntansha): HAMAGUCHI Munehiro Faculty of Dentistry, Osaka University Assistant, 歯学部, 助手 (50248019) ; IIDA Seiji Dental Hospital, Osaka University Assistant Professor, 歯学部・附属病院, 講師 (40283791) ; KOGO Mikihiko Faculty of Dentistry, Osaka University Associate Professor, 歯学部, 助教授 (20205371)
• Project Period (FY): 1998 – 1999
• Keywords: trigeminal / NMDA / rhythmical jaw movement / embryonic / patch clamp

Research Abstract

We analyzed the trigeminal neural circuit related to rhythmical jaw movements.
We used neonatal rats. We used in vitro isolated brainstem block preparation and whole cell patch clamp technique. Results as follows
1. We found rhythmical EPSP on membrane potentials of trigeminal motoneurons, which were thought to be originated from rhythm generators.
2. N-methyl D-aspartate (NMDA) receptor agonist, NMA application induced those EPSPs. NMDA receptor must be involved in the rhythm generation circuit.
3. In embryonic stages, trigeminal rhyrhmical activities were generated in E-20. In E-18,19, the rhythmical activities were incompletely recognized. However, rhythmical EPSPs were regularly recognized. In E-16,17, the rhythmical activities were not generated. It is likely that the rhythm generation circuit is developed at E-18,19.