Project/Area Number |
01570966
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
Otorhinolaryngology
|
Research Institution | Medical Research Institute, Kanazawa Medical University |
Principal Investigator |
SATO Kiichi Med. Res. Inst., Kanazawa Med. Univ., Professor, 総合医学研究所, 教授 (60102034)
|
Project Period (FY) |
1989 – 1990
|
Project Status |
Completed (Fiscal Year 1990)
|
Budget Amount *help |
¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1990: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1989: ¥600,000 (Direct Cost: ¥600,000)
|
Keywords | hypoxia / acute sensorineural hearing loss / auditory brainstem response (ABR) / hair cell / stria vasularis / succimic dehydrogenase / latic dehydrogenase / transmission electronmicroscope / 乳酸脱水素酵素 |
Research Abstract |
The Author has investigated the changes of auditory brainstem response (ABR) and their histochemical activities of hair cells, and electronmicroscopic changes in the anoxic guinea pigs in making observation of the arterial blood pressure (ABP), the ECG and the rectal temperature. The hypoxic condition was inducted by alternate inhalation of 2 minutes' mixture of 5%O_2 and 95%N_2, and room air. The results are as follows. In the hypoxic condition, the ABR wave became flat, the ABP fell, PaO_2 decreased and PaCO_2 increased. The activities of succinic dehydrogenase increased and lactic dehydrogenase increased using the intravital histochemical investigation. However the morphological alteration of hair cells was not observed. The transmission electronmicroscopic study clarified that the marked edema of intermediate cells of stria vascularis and discharge of interdigitation between marginal cell and intermediate cell of stria vascularis. As the results of this study, the author suggested that hypoxic condition caused the change of stria vascularis and this change was one of the etiology of acute sensorineural hearing loss.
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