| Kainic Acid에 의해 나타나는 흰쥐 해마 신경원의 독성변화 |
| 장세희, 김두응,권오상,김경용,이원복,김동창 |
| 중앙대학교 신경과, 해부학. |
| Excitotoxic change of Hippocampal Neuron by Kainic Acid in Rat ?Brain |
| Sei Hee Chang, M.D., Doo Eung Kim, M.D., Oh Sang Kwon, M.D., Kyung Yong Kim, M.D., Won Bok Lee, M.D., Dong Chang Kim, M.D. |
| Department of Neurology, College of Medicine, Chung-Ang University, Department of Anatomy, College of Medicine, Chung-Ang University |
|
|
|
|
| Abstract |
|
The excitotoxic effect of kainic acid on dendrites and neuronal cell bodies of hippocampus and dentate gyrus was studied with time (1, 4, 8, 16 hours, 2, 7, 14 days) light and electron microscopically by intraperitonial injection into rat. The results obtained were as follows. 1) The acute dendrotoxic effect was observed as laminar pattern of swelling along pyramidal cell body layer and dendritic fields and was most prominently at 2-4 hours after kainic acid injection. In ultractructural study, the acute change occurred in dendrites of pyramidal cells in hipocampus because the synapses between nerve terminals and swollen components were not destroyed and remained intact and, identified the swollen structures as dendrites. So, it was obvious from the results that the acute change by kainic acid was osmolysis and was continued till initial 4 hours but was finally faded out. 2) The distribution of kainic acid receptor within hippocampus was different because the prominent dendritic swelling occurred in proximal basilar dendritic field of CA 3 and 4 and the proximal and distal basilar dendritic fields of CA 1 and 2, and no change was observable in dentate granule cell. The sensitivity of hippocampal dendritic fields to kainic acid could be put in decreasing order as CA3, CA4, CA1, CA2 and dentate granule cell 3) With the elapse of time, the acute change disappeared and pyramidal cells began to degenerate by the chronic reaction about 7 days after kainic acid injury, and the pyramidal cell density in CA regions greatly decreased. Almost all pyramidal cells degenerated the dentate granule cells were not affected to kainic acid throughout the time. In conclusions, hippocampal neurons were postulated to be very sensitive to kainic acid, and in contrast to the gradual disappearance of acute change within several hours, the degeneration of pyramidal neurons by chronic change was developed within several days regardless of acute change. |
|
PDF Links
Full text via DOI
Download Citation
