1992 Fiscal Year Final Research Report Summary
Study on the modulation of temperature signals from the skin by the nucleus raphe magnus and subcoeruleus
| Project/Area Number |
03670082
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
環境生理学(含体力医学･栄養生理学)
|
|---|
| Research Institution | Chukyo Women's University (1992)
Nagoya City University (1991) |
|---|
Principal Investigator |
SATO Haruhiko Chukyo Women's University Physical Education TITLE OF POSITION : professor, 体育学部, 教授 (20080004)
|
|---|
| Project Period (FY) |
1991 – 1992
|
| Keywords | dorsal horn neurons / temperature signals / raphe nucleus / subcoeruleus / serotonergic / noradrenergic / Methysergide / thermoregulation |
|---|
| Research Abstract |
1. Extracellular recordings were made from dorsal horn cells responsive to temperature changes in the innocuous range (10-40ﾟC) of scrotal skin temperature in the lumbosacral segment of urethane-anesthetized rats. The temperature responsive dorsal horn cells (65) were classified into two groups : warm-responsive cells (48) showing an increase in firing rate by skin warming, warm-response, and cold-responsive cells (17) showing an increase in firing rate by skin cooing, cold-response. The effects of electrical stimulation in the nucleus raphe magnus (NRM) and subcoeruleus (SC) on their firing activity were studied.
2. Effect of electrical stimulation in the NRM as well as in the SC was found to be characterized by a partial or complete depression of warm- or cold-responses. The background activity mostly remained unaffected.
3. Depression of temperature response occurred in most (95%) of warm-responsive cells by NRM stimulation, whereas in the majority (79%) of cold-responsive cells by SC stimulation.
4. In four warm-responsive cells, NRM-evoked depression of their temperature responses was partially antagonized by Serotonin antagonist, Methysergide (1 mg/kg, i.v.). Such NRM-evoked depression was suggested to be mediated by serotonergic raphe-spinal pathways.
5. The results suggest that the raphe- and subcoeruleo-spinal pathways descendingly modulate the spinal transmission of warm and cold signals contributing to central thermoregulation.
|
