Project/Area Number |
02670826
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
Functional basic dentistry
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Research Institution | Tokyo Medical and Dental University, Faculty of Dentistry. |
Principal Investigator |
TODA Kazuo Department od physiology, Faculty of Dentistry, Tokyo Medical and Dental University, LECTURER, 歯科部, 講師 (80134708)
|
Project Period (FY) |
1990 – 1991
|
Project Status |
Completed (Fiscal Year 1991)
|
Budget Amount *help |
¥2,600,000 (Direct Cost: ¥2,600,000)
Fiscal Year 1991: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1990: ¥1,900,000 (Direct Cost: ¥1,900,000)
|
Keywords | periaqueductal gray matter / somatosensory area / noxious stimulation / wide dynamic range neuron / wind up / serotonin / morphine / rat / 大縫線核 / 受容野 / ワインドアップ |
Research Abstract |
Characteristics of somatosensory inputs to the periaqueductal gray matter (PAG) neurons were investigated using barbiturate-anesthetized Wistar albino rats. Results were as follows : (1) there were at least 2 types of PAG neurons according to their receptive fields. One was large type (PAG-L), and the other was small type (PAG-S). (2) Both types of neurons were activated by nonoxious (touch/ heat) and noxious (mechanical, heat and chemical) stimulation. (3) In a majority of PAG-L type neurons, wind-up phenomenon was observed. (4) Microiontophoretically applied morphine onto the PAG-S type neurons increased their spontaneous activities. (5) The threshold value of noxious heat stimuli applied to the PAG-S type neurons was higher than that applied to the PAG-L type neurons.
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