항염증성 약물의 치태추출액에 대한 중성 호성백혈구의 화학주성억제 효과에 관한 시험적 연구

우진오 서울大學校 大學院 1981 국내석사

Effect of bisphosphonates on the expression of OPG and OPGL in mouse calvarial osteoblastic cells : Bisphosphonates계열의 약물이 마우스 두개관 조골세포 유사세포의 OPG와 OPGL 발현에 미치는 영향

김용희 Seoul National University 2001 국내석사

Regulatory mechanism of high extracellular Ca²+ on RANKL expression in mouse osteoblastic cells : 고농도 세포외 Ca²+의 마우스 조골세포 RANKL발현 조절기전

김진미 서울대학교 대학원 2002 국내박사

인슐린이 AMPA로 인한 뇌 세포 손상을 억제하는 기전에 관한 연구

한용 경희대학교 대학원 2002 국내석사

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. 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.

Effect of high extracelluar Ca²[+] on the differentiation of osteoclast : 고농도 세포외 Ca²[+]이 파골세포 분화에 미치는 영향

박혜영 Seoul National University 2001 국내박사

조골세포에서 인슐린에 의해 유도되는 유전자 발현연구

한수희 경희대학교 대학원 2006 국내박사

Effects of allopregnanolone on GABAA receptors in hippocampal neurons : 해마신경세포에서 GABAA 수용체에 대한 allopregnanolone의 효과

박혜미 경북대학교 대학원 2010 국내석사

3-Hydroxy, 5-reduced pregnane steroids, such as allopregnanolone (AlloP) and tetrahydro-deoxycorticosterone, are potent modulators of GABAA receptors and affect many biological responses including sedative, anxiolytic, anticonvulsant and anesthetic actions. Although it has been well established that these neurosteroids preferentially modulate postsynaptic GABAA receptors to decrease the neuronal excitability, the neurosteroid modulation of extrasynaptic and presynaptic GABAA receptors is poorly known. In the present study, we have investigated the multiple effects of AlloP on GABAA receptor-mediated inhibition in acutely isolated hippocampal CA3 pyramidal neurons by use of a conventional whole-cell patch-clamp technique. Extracellularly, but not intracellularly, applied AlloP (≥30 nM) induced the membrane Cl- currents, which were mediated by GABAA receptors, even in the presence of competitive GABAA receptor antagonist, suggesting that AlloP binds to GABAA receptors in the outer leaflet of lipid bilayer, which is different from the GABA-binding sites. In addition, the intracellular loading of -cyclodextrin (500 M), which efficiently sequesters several kinds of naturally occurring neurosteroids including AlloP, significantly decreased the amplitude of picrotoxin-sensitive holding currents mediated by extrasynaptic GABAA receptors. Furthermore, AlloP (30 nM) significantly increased the frequency of GABAergic spontaneous inhibitory postsynaptic currents in voltage-dependent Na+ and Ca2+ channel-dependent manners, suggesting that AlloP acts presynaptic GABAA receptors to depolarize GABAergic nerve terminals. These results suggest that AlloP, one of representative endogenous neurosteroids, via the modulation of multiple types of GABAA receptor-mediated inhibition, decreases the neuronal excitability, and thus exerts its pharmacological as well as pathophysiological actions.

Pregnenolone sulfate enhances spontaneous glutamate release via the induction of presynaptic Ca2+-induced Ca2+ release : 해마 hilar 신경세포에서 Pregnenolone sulfate에 의한 자발적 글루타민산 방출 증가

이근희 경북대학교 대학원 2010 국내박사

Pregnenolone sulfate (PS) acts as an excitatory neuromodulator and has a variety of neuropharmacological actions, such as memory enhancing and convulsant effects. In the present study, we have investigated the effect of PS on glutamatergic spontaneous excitatory postsynaptic currents (sEPSCs) in acutely isolated dentate gyrus hilar neurons by use of a conventional whole-cell patch-clamp technique. PS significantly increased sEPSC frequency in a dose-dependent manner without affecting the current amplitude, suggesting that PS acts presynaptically to increase the probability of spontaneous glutamate release. However, known molecular targets of PS, such as ??7 nicotinic ACh, NMDA, ??1 receptors and voltage-dependent Ca2+ channels, were not responsible for the PS-induced increase in sEPSC frequency. Whereas, the PS-induced increase in sEPSC frequency was completely occluded in the Ca2+-free external solution, and significantly reduced by either the depletion of presynaptic Ca2+ stores or the blockade of ryanodine receptors, suggesting that PS elicits Ca2+-induced Ca2+ release (CICR) within glutamatergic nerve terminals. In addition, the PS-induced increase in sEPSC frequency was completely occluded by transient receptor potential (TRP) channel blockers. These data suggest that PS increases spontaneous glutamate release onto acutely isolated hilar neurons via presynaptic CICR, which was triggered by the Ca2+ influx passing through presynaptic TRP channels. The PS-induced modulation of excitatory transmission onto hilar neurons would have a broad impact on the excitability of hilar neurons and thus affect the pathophysiological functions mediated by the hippocampus.

Possible involvement of DNA methylation in NKCC1 gene expression during postnatal development : 쥐의 대뇌피질에서 후생유전학적 변화에 의한 NKCC1 발현 조절

이해암 경북대학교 대학원 2010 국내박사

후생유전학적 변화에 의한 유전자 발현 조절에 대한 연구는 주로 암에서 종양억제 유전자를 대상으로 진행되었으나 최근에는 그와 더불어 신경세포에서의 후생유전학에 대한 연구가 활발히 이루어 지고 있다. 특히 DNA 메틸화에 의한 특정 유전자의 발현조절과 chromatin remodeling에 관여하는 인자들에 대한 연구가 진행되고 있다. 본 연구에서는 쥐의 대뇌피질에서 신경 세포 내의 염소이온 농도를 조절하여 GABA에 의한 흥분성 또는 억제성 반응을 유도하는 transporter의 후생유전학적 변화에 대해 조사하였다. 쥐의 대뇌 피질은 발달 초기 NKCC1의 발현이 높고 KCC2의 발현이 낮아 세포 내에 상대적으로 높은 농도의 염소이온을 가지게 되지만 발달이 진행됨에 따라 NKCC1의 발현이 감소하고 KCC2의 발현이 높아져 세포 내의 염소이온 농도가 낮아지게 된다. 발달에 따른 KCC2의 발현을 유도하는 기전에 대한 보고는 많이 있지만 NKCC1의 발현이 줄어드는 기전에 대한 보고는 전무하다. NKCC1의 exon1 앞부분에는 여러 개의 CpG가 조밀하게 존재 하므로 후생유전학적 변화에 의해 NKCC1의 발현이 조절 될 가능성은 매우 높았으므로 MS-PCR, COBRA, bisulfite sequencing 방법으로 메틸화를 조사하였다. 먼저 luciferase assay를 이용하여 NKCC1 프로모터 영역을 클로닝 하고 NKCC1 프로모터 영역의 메틸화를 조사한 결과 발달이 진행 됨에 따라 메틸화가 증가하였고 그 정도는 NKCC1 mRNA와 단백질의 발현과 반비례하여 나타남을 알 수 있었다. 또한 DNA 메틸화를 유도하는 효소인 DNMT와 메틸화된 DNA에 결합하는 MBD들의 발현도 매우 유동적임을 알 수 있었다. DNA 메틸화와 히스톤 탈 아세틸화가 NKCC1의 발현에 미치는 영향을 조사한 결과 DNA 탈 메틸화 및 히스톤 아세틸화는 각각 NKCC1의 발현을 증가 시켰고 둘을 동시에 유도하였을 경우 상승효과가 나타남을 확인 하였다. 반면 KCC2 발현은 DNA 탈 메틸화 및 히스톤 아세틸화에 영향을 받지 않는 것으로 나타났다. 신경세포에 손상을 유도할 경우 NKCC1의 재발현이 유도되는 보고가 있어, 태어난 지 30일이 넘은 쥐의 우측 총경동맥을 통해 나일론 섬유를 삽입하여 우측 중뇌동맥을 폐쇄하여 허혈성 뇌 손상 동물모델을 만들고 대뇌피질에서의 NKCC1 발현을 조사한 결과 뇌 손상을 입은 쪽의 대뇌피질에서 NKCC1의 발현이 현저히 증가하는 것을 확인 하였다. COBRA와 bisulfite sequencing을 이용하여 뇌 손상을 입은 쪽의 대뇌피질과 손상을 입지 않은 대뇌피질에서 NKCC1 프로모터 영역의 메틸화를 조사한 결과 손상을 입은 대뇌피질에서 현저한 탈 메틸화가 유도됨을 확인 하였다. 이러한 결과들을 종합하면, NKCC1 프로모터 영역은 발달에 따라 메틸화가 증가하여 NKCC1의 발현을 감소시키고 결과적으로 세포 내의 염소이온 농도를 낮추게 되며, 뇌 손상을 입었을 경우 프로모터 영역의 탈 메틸화가 유도되고 NKCC1의 재발현을 유도하게 되는 것을 알 수 있다. 앞으로의 연구는 포유류에서 탈 메틸화를 유도하는 효소의 동정과 NKCC1 프로모터 부위에 결합하는 MBD 또는 전사억제 인자를 밝히고 chromatin remodeling에 관여하는 단백질을 밝히는 것이 필요 할 것으로 사료된다.

천궁에 의한 진통효과의 약리작용연구

김준회 경희대학교 대학원 2006 국내석사