| Project/Area Number |
06671852
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Functional basic dentistry
|
|---|
| Research Institution | Niigata University |
|---|
Principal Investigator |
MIYAOKA Yozo Niigata University, Department of Physiology, Assistant Professor, 歯学部, 助手 (10134941)
|
|---|
| Project Period (FY) |
1994 – 1995
|
| Project Status |
Completed (Fiscal Year 1995)
|
| Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1995: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1994: ¥1,200,000 (Direct Cost: ¥1,200,000)
|
|---|
| Keywords | behavioral analysis / neurophysiology / taste threshold / lingual movement / licking / brain stem / taste neurons / taste centers / 舌運動 / 味覚運動反応 / 橋味覚野 / ラット |
|---|
| Research Abstract |
Ingestive behavior of gustatory solutions was investigated using freely moving rats. Wistar rats with intact and electrically-lesioned pontine taste areas (PTA) were used. Prior to testing, these animals were subject to water deprivation to be motivated to fluids. Bottles filled with distillled water (DW) and the four basic taste solutions were presented to the animals. Intra-bottle pressure changes were monitored as an index of licking. Behavioral experiments showed that PTA-lesioned as well as PTA-intact rats licked DW and a 0.5 M sucrose solution from the bottles with a rhythmic and constant pattern. On the other hand, PTA-intact rats rejected 0.5 M sodium chloride (NaCl) and 0.01 M quinine hydrochloride (QHCl) solutions, but PTA-lesioned rats often licked these two solutions with an intermittent pattern. Both PTA-intact and PTA-lesioned rats were likely to use olfactory information rather than gustatory to determine ingestive behavior of a 0.03M hydrochloric acid solution. Responses of PTA neurons to DW and the four basic taste solutions applied to the oro-pharynx also were investigated in rats with intact- and sectioned-chorda tympani nerves (CTN) which transmit gustatory information from the anterior tongue to the central nervous system. The NaCl, HCl, and QHCl solutions were effective in evoking responses in PTA neurons, but DW and the sucrose solution were less effective either in CTN-intact or in CTN-sectioned rats. The effectiveness of the NaCl, HCl, and QHCl solutions were greater in CTN-sectioned rats compared with CTN-intact. The results obtained from the behavioral and neurophysiological experiments conducted in the present investigation suggest that gustatory information from the posterior tongue and pharynx may play a role in determining gustatory-evoked ingestive behavior.
|
