• The Korean Journal of Physiology and Pharmacology
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• v.5 no.6
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• pp.467-477
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• 2001

We examined astrocyte regional heterogeneity in their morphological changes in response to various stimuli. Astrocytes were cultured from six different neonatal rat brain regions including cerebral cortex, hippocampus, cerebellum, mid brain, brain stem and hypothalamus. Astrocyte stellation was induced by serum deprivation and the maximum stellation in different regional astrocytes was achieved after 2 h. After 24 h, in all astrocyte cultures, the level of stellation returned to their original level. Cerebellar or hypothalamic astrocytes were the most or the least sensitive, respectively, to serum deprivation. The order of maximum sensitivity to serum deprivation among different regional astrocytes was: cerebellum＞mid $brain{\ge}hippocampus,\;brain\;stem{\ge}cerebral$ cortex＞hypothalamus. Isoproterenol-induced astrocyte stellation was also examined in different regional astrocytes, and similar order of maximum sensitivity as in serum deprivation was observed. Next a possible developmental effect on astrocyte morphological changes was examined in cerebral cortex and cerebellum astrocytes cultured from postnatal day 1 (P1), P4 and P7 rat brains. A much higher sensitivity of cerebellum astrocytes to serum deprivation as well as isoproterenol treatment was consistently observed in P1, P4 and P7-derived astrocytes compared to cerebral cortex astrocytes. The present study demonstrates different regional astrocytes maintain different levels of morphological plasticity in vitro.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2003.10a
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• pp.123-123
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• 2003

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.123-123
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• 2003

Primary cultures of rat fetus brain exhibit phenotypes of neuron, oligodendrocyte, and astrocyte from "neurospheres". To understand the role of mitogen-activated protein kinase (MAPK) cascade and gap junctional intercellular communication (GJIC) in the differentiation of neurosphere-derived astrocyte, we investigated the effects of 12-O-tetradecanoylphorbol-13-acetate (TPA) on the cultured astrocyte morphology.(omitted)

• Journal of Ginseng Research
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• v.28 no.2
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• pp.120-126
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• 2004

Glial cells such as astrocytes and microglial cells are the main source of proinflammatory cytokines and nitric oxide(NO) in the central nervous system, which exert neuroimmune and inflammatory functions and other various neurobiologic effects. Though Panax ginseng C.A. Meyer has been known to strengthen the body's defence mechanisms and also to maintain the homeostasis in the central nervous system, the effects of Panax ginseng on the production of immune and inflammatory mediators have not been studied well in the brain. Therefore, this study was designed to study the effects of ginseng saponins on the production of proinflammatory cytokines and NO in the primary cultures of mixed glial cells. White ginseng saponin, 200-500 $\mu$g/ml, showed significant cytotoxicity after 72 hrs and increased TNF-$\alpha$, IL-$\beta$, and NO production. Lower doses of 50-100 $\mu\textrm{g}$/ml showed little cytotoxicity until 72 hrs and also increased the production of TNF-$\alpha$, IL-1$\beta$, and NO. Triple immune staining showed that white ginseng saponin, 200$\mu\textrm{g}$/ml for 72 ks, induced stellation of astrocytes and iNOS expression exclusively in microglial cells. Taken together, the white ginseng saponin increased the production of proinflammatory cytokines such as TNF-$\alpha$ and IL-1$\beta$, and induced iNOS expression and NO production in mixed glial cell cultures, which may be ascribed to the enhancement of central immune responses and the regulation of inflammatory reactions by Panax ginseng.