인슐린이 AMPA로 인한 뇌 세포 손상을 억제하는 기전에 관한 연구 = Inhibition of AMPA-induced neuronal damage by insulin

다국어 초록 (Multilingual Abstract)

This study was conducted 1) to investigate variability in adaptability, growth, needle morphology and wood property of 24 Norway spruce provenances introduced from Germany and Rumania and DNA polymorphism among the trees of the provenances based on PCR and 2) to select provenances with best adaptability, growth and wood property for planting in Korean environmental conditions.
Seeds of the provenances were sown in the nursery of Institute of Forest Genetics in 1976 and 1977. In 1980, seedlings were lifted as 2-2 or 1-2 stock from the nursery and planted in seven different locations in Korea. For all locations a randomized complete-block design was used with 5-tree x 5-tree square plots and three replications.
The results obtained from this study were summarized as follows:
1. There were significant variations in number of seeds / gram, weight / 1,000 seeds, and germination rate among the provenances. The rates of germination of provenances in laboratory condition were correlated positively with latitudes but negatively with longitudes of the seed origin.
2. Significant differences in cold injury in the nursery over two years were found among provenances. The percentage of cold injury of the provenances was positively correlated with latitudes of the seed origin, however, it was negatively correlated with longitudes and altitudes of the seed origin.
3. There were significant differences among provenances in the year of test plantation establishment and also at the ages of 7, 12 and 15. In the year of plantation establishment survivals of the German provenances were better than that of Rumanian provenances at most plantations. The survival of provenances was correlated positively with the latitudes of the seed origin but negatively with the longitudes of the seed origin. In general, the survival of the seedlings in the year of plantation establishment were better on the plantations with higher soil silt content and annual precipitation and located in higher latitudes and altitudes.
4. The survival of the provenances at the age of 15 was also correlated positively with the latitudes of the seed origin but negatively with the longitudes as well as the altitudes of the seed origin. Generally, the survival of the trees was still better on the plantations with higher annual precipitation and located at higher altitudes while the survival was poor on the plantations with higher soil clay content.
5. Significant differences in height and diameter growth were if found among provenances as well as among plantations. For height and diameter growth, best provenances were provenances 10 and 14 from Germany while poorest provenances were provenances 046 and 048 from Rumania. Provenance rank in height and diameter growth fluctuated significantly from age to age. Height and diameter growth of provenances were significantly correlated with latitudes of the seed origin, survival and germination rate. However, height and diameter growth of provenances were negatively correlated with longitudes of the seed origin. Generally, height and diameter growth were positively correlated with altitude, soil silt and mineral contents, C.E.C. and soil pH as well as climatic factors such as relative humidity, annual number of foggy days at the plantations. The growth of Norway spruce trees were affected mostly by the silt and sand contents in soil of the plantation followed by in the order of the amount of organic matter, total nitrogen content, Mg++ content in soil, soil pH, annual number of foggy days and relative humidity at the plantation.
6. For all plantations significant differences in fresh and dry weight of trees were found among provenances. Provenances 10, 14 and 19 from Germany were the highest biomass producing provenances while provenance 047 from Rumania was the poorest in biomass production.
7. Significant among provenance differences were found for needle characteristics such as length, width, thickness, density of stomata/㎟, curvature and number of needles / 5cm of shoot. The needle curvature of provenances were correlated positively with latitudes of the seed origin but negatively with longitudes and altitudes of the seed origin. Needle curvature had positive correlations with height and DBH and fresh weight. The needle width and thickness had positive correlations with the latitudes of the seed origin but they had negative correlations with DBH and dry weight of trees. Number of stomata/㎟ had negative correlations with height, fresh and dry weight of trees.
8. There were also large provenance variation in wood properties such as annual ring width, specific gravity and tracheid length. Specific gravity had negative correlations with height, DBH, dry weight and annual ring incrememt. On the other hand, tracheid length had positive correlations with height, diameter at root collar and dry weight. Tracheid length varied significantly from plantation to plantation indicating that environmental condition could affect tracheid length significantly.
9. Of the three random primers used for PCR only one primer (primer I) revealed an extensive DNA polymorphism among the trees of the provenances. One band size of 1.4kb was appeared to be common for all trees of provenances and two polymorphic bands(size of 830bp and 1.9kb) that could be used for identifying clones were found.

다국어 초록 (Multilingual Abstract)

In the present study, we designed a series of experiments to explore neuroprotective effects of insulin.
Insulin significantly inhibited the AMPA-induced neuroblastoma cell damage in MTT assay. However, insulin had little effects on the AMPA-induced glial cell damage. To determine if insulin has inhibitory effect on AMPA-induced exitotoxicity, we designed grease-gap recording assays using rat brain slice. In this experiment, insulin had significantly shown to inhibit AMPA-induced depolarization. In the flow cytometry and DNA fragmentation assays, insulin also had shown to inhibit AMPA-induced DNA breakdown. Interestingly, insulin reduced activities of SAPK/JNK which was stimulated by AMPA; however, it was found that AMPA could not decrease the insulin-stimulated Akt activity.
Taken together, these results suggest that insulin has neruoprotective effects by inhibiting AMPA-induced exitotoxicity and apoptosis, possibly via activating Akt and/or blocking SAPK/JNK.

목차 (Table of Contents)

• 목차
• 목차 = i
• 그림목차 = ii
• 국문요지 = iii
• I. 서론 = 1
• II. 실험재료 및 방법 = 4
• 1. 실험동물 및 시약 = 4
• 2. 세포배양 = 4
• 3. MTT assay를 통한 세포사멸 검사 = 4
• 4. Grease-gap recording assay를 통한 세포의 탈분극 정도 측정 = 5
• 5. PI 염색에 의한 apoptosis 분석 = 5
• 6. DNA 추출 및 전기영동 = 6
• 7. Western blotting 분석 = 7
• 8. 통계처리 = 7
• III. 실험결과 = 8
• 1. Insulin이 신경세포에서 AMPA로 인한 사멸을 억제하는 효과 = 8
• 2. Insulin이 brain-slice에서 AMPA로 인한 탈분극을 억제하는 효과 = 8
• 3. AMPA에 의한 신경세포의 apoptosis 유도 및 insulin에 의한 억제 = 9
• 4. AMPA로 인한 신경세포의 사멸을 억제하는 인슐린의 신호전달기전 = 9
• IV. 고찰 = 10
• V. 결론 = 17
• 참고문헌 = 18
• Abstract = 30