1998 Fiscal Year Final Research Report Summary
Analysis of trigeminal rhythm generation circuit in brainstem
| Project/Area Number |
09832006
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
咀嚼
|
|---|
| Research Institution | Osaka University |
|---|
Principal Investigator |
KOGO Mikihiko Osaka University, Faculty of Dentistry, Associate Professor, 歯学部, 助教授 (20205371)
|
|---|
| Project Period (FY) |
1997 – 1998
|
| Keywords | Trigeminal nerve / Mastication / rhythm generator / central pattern generator / brainstem |
|---|
| Research Abstract |
We made jaw attached brainstem block preparation in vitro and analyzed chemically induced rhythmical jaw movements with CCD camera.After application of N-methyl- D,L-aspartate(NMA)(20-4OmuM) combined with gamma-aminobutyric acid (GABA)_A antagonist, bicuculline methiodide (BIG) (5-10 muM), rhythmical jaw movements were observed.Muscle contractions of masseter and digastric muscles were also recognized with CCD camera.EMG activities of these muscles were observed after application of NMA- BIC(NMA4O muM, BIG10 muM).In the second series of experiments, we used patch clamp method.Rhythmical discharges of trigeminal motoneurons were synchronized with extracelluler discharges of peripheral trigeminal motor nerve.Only the NMA application cab induce rhythmical EPSP.Additional BIC application induce action potentials in the trigeminal motoneurons.Effect of norepinephrine and serotonine on the rhythmical trigeminal activities were also analyzed.alpha_1 adrenoreceptor agonist and 5HT_2 receptor agonist enhanced the rhythm circuitry, while alpha_2 adrenoreceptor agonist and 5HT_1 receptor agonist suppressed them.
|
