• 생물정신의학
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• 제10권2호
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• pp.126-132
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• 2003

Objectives:The purpose of this study is to examine the effects of venlafaxine, one of novel antidepressant drugs, on neurite growth in PC12 cells. Methods:PC12 cells were cultured with NGF for eight days. Then different concentrations($0{\mu}M$, $1{\mu}M$, $5{\mu}M$) of venlafaxine were mixed with cultured PC12 cells. After 24 hours and 48 hours of culture, we compared the effects of venlafaxine on the total length of neurites of cultured PC12 cells between no venlafaxine treated group($0{\mu}M$) and venlafaxine treated groups($1{\mu}M$ and $5{\mu}M$). Additionally, we studied the concentration-dependent effect of venlafaxine on differentiation in PC12 cells. Results:Experimental results showed that 1) the mean length of neurites in $1{\mu}M$ and $5{\mu}M$ venlafaxine treated group was more increased than no venlafaxine treated group(p=0.002). 2) the length of neurite in $5{\mu}M$ venlafaxine treated group was more elongated than $1{\mu}M$ venlafaxine treated group(p=0.046). 3) the length of neurite in $6{\mu}M$ venlafaxine treated group was more elongated than all the other concentrations in our experiment. Above $6{\mu}M$, the length of neurite was shortened in inverse proportion to the concentration of venlafaxine. Conclusions:This results suggest that venlafaxine, one of novel antidepressant drugs, promotes the differentiation of neuron. This study is believed to be a first step toward understanding the molecular and cellular mechanisms of antidepressant treatment.

• 대한약리학회지
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• 제29권2호
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• pp.165-174
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• 1993

칼슘이온은 신경섬유 성장의 중요한 조절인자이나 그 정확한 작용기전은 불명확하다. 세포골격 단백은 in vivo 및 in vitro에서 칼슘의존성 단백분해효소(칼파인)에 의해 신속히 분해되므로, 칼슘이온에 의한 신경섬유의 퇴행에 있어서 칼파인의 관련성을 추구하기위하여, 배양된 해마신경세포에서 칼슘이온 ionophore인 A23187에 의한 신경섬유의 성장억제가 칼파인의 억제제인 EST 및 MDL 28170에 의해 차단되는지를 조사하였다. A23187은 100nM의 농도에서 축삭에는 영향이 없이 수상돌기의 퇴행을 유발하였으나, 300 nM의 농도에서는 축삭의 성장을 억제하였다. EST(5 혹은 20 uM) 및 MDL 28170(20 uM)은 100 nM A23187의 수상돌기에 대한 작용과 300 nM A23187의 축삭에 대한 작용을 효과적으로 차단하였다. EST는 A23187에의한 세포내 칼슘이온의 증가를 차단하지 못하였다. 이상의 결과는 해마추상체세포에서 칼슘에 의한 신경섬유의 퇴행이 칼파인에 의해 매개됨을 시사한다.

• BMB Reports
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• 제31권5호
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• pp.468-474
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• 1998

Membrane depolarization in PC12 cells induces calcium influx via an L-type voltage-sensitive calcium channel (L-VSCC) and increases intracellular free calcium, which leads to tyrosine phosphorylation of epidermal growth factor (EGF) receptor and the associated adaptor protein, She. This activated EGF receptor complex then can activate mitogen-activated protein (MAP) kinase, as in nerve growth factor (NGF) receptor activation. In the present study, we investigated the role of EGF receptor in the signaling pathway initiated by membrane depolarization of PC12 cells. Prolonged membrane depolarization induced phosphorylation of extracellular signal-regulated kinase (ERK) within 1 min in undifferentiated PC12 cells. Pretreatment of PC12 cells with the calcium chelator EGTA abolished depolarization-stimulated ERK phosphorylation, but NGF-induced phosphorylation of ERK was not affected. The chronic treatment of phorbol ester, which down-regulated the activity of protein kinase C (PKC), did not affect the phosphorylation of ERK upon depolarization. In the presence of an inhibitor of EGF receptor, neither depolarization nor calcium ionophore increased the level of ERK phosphorylation. These data imply that the EGF receptor is functionally necessary to activate ERK and neurite outgrowth in response to the prolonged depolarization in PC12 cells, and also that PKC is apparently not involved in this signaling pathway.

• 한국잠사학회:학술대회논문집
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• 한국잠사학회 2003년도 International Symposium of Silkworm/Insect Biotechnology and Annual Meeting of Korea Society of Sericultural Science
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• pp.99-99
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• 2003

Brain-derived neurotrophic factor (BDNF) induced a significant neurite extension of antennal lobe (AL) neurons from the silk moth Bombyx mori in culture on lamini/ concanavalin A-coated dishes, in comparison with smaller effect of 20-hydroxyecdy-sone (20-HE). But the effect fur neurite extension by 5-hydroxytryptamine (5-HT) could not be found. A significant increase in the number of new primary branches from the principal neurites of AL neurons was also shown in culture with BDNF and 5-HT, but not with 20-HE. (omitted)

• 혜화의학회지
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• 제25권1호
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• pp.37-44
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• 2016

Objectives : This study was designed to investigate the effect of Gamishinchubogun-tang (JiaweiShenzhuibujian-tang; GSB) on regeneration of PC12 cells. Methods : PC12 cells have been used extensively as a model for studying the cellular and molecular effects of neuronal cells. In order to check the effect of GSB on the regeneration of PC12 cells, the morphological change of PC12 cells were observed comparatively in GSB group and control group. Results : The significant changes in neurite length of PC12 cells have been observed on GSB group. In proportion to the concentration of GSB it was observed an increase in neurite outgrowth. Conclusions : This study confirmed that GSB made a significant influence on regeneration of PC12 cells.

• Biomolecules & Therapeutics
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• 제8권4호
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• pp.285-292
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• 2000

The effects of the members of the same nuclear receptor superfamily (all-trans retinoic acid (RA), thyroid hormone(T3) or hydrocortisone) on proliferation and differentiation in the SK-N-SH neuroblastoma (NB) cell lines were studied. NB cells were treated with RA, T3, or hydrocortisone at concentration of 10$^{-6}$ M or 10$^{-8}$ M for 3 days or 7 days. RA induced concentration- and time-dependent morphologic differentiation(neurite outgrowth and microtubule-associated protein expression) and growth inhibition in NB cells. Treatment of 10$^{-7}$ M T3 for 7 days increased viability and differentiation of NB cells. Treatment of 10$^{-6}$ M hydrocortisone for 7 days increased viability of NB cells. Although these three effectors are members of the same receptor superfamily, the regulation of brain development may be carried out in a different manner.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2005년도 춘계학술대회 논문집
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• pp.3-8
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• 2005

We introduced mechanical stimuli and micropatterned substrate with micro fibers to investigate the effects of those on neurite outgrowth along with nerve growth factor (NGF) in vitro. Microfiber substrates were fabricated using an electrospinning process. And PC-12 cells cultured on substrates were simulated with nerver growth factor and laminar flow shear stress in a fluid flow system The results suggest that microfiber substrates and fluid-induced shear stress are promising for simulating neuronal regeneration in a desired direction.

• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1490-1495
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• 2009

The development of nanotechnology has penetrated the fields of biology and medicine, resulting in remarkable applications for tissue regeneration. In order to apply this technology to tissue engineering, we have developed nano-scaled 3D scaffolds consisting of growth factor-loaded heparin/poly(l-lysine) nanoparticles (NPs) attached to the surface of polymeric micro spheres via polyionic complex methods. Growth factor-loaded NPs were simply produced as polyelectrolyte complexes with diameters of 100-200 nm. They were then coated onto positively charged poly(lactic-co-glycolic acid) (PLGA) pretreated with polyethyleneimine to enable cell adhesion, proliferation, and stimulation of neurite outgrowth. Propidium iodide staining and $\beta$-tubulin analysis revealed that neuronal PC12 cells proliferated extensively, expressed significant amounts of b-tubulin, and showed well-structured neurite outgrowth on polymeric microspheres by stimulation with growth factors. These results suggest that cellular adhesion and biological functionality on prepared PLGA microspheres enabled terminal differentiation of neuronal cells.

• 대한의생명과학회지
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• 제13권3호
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• pp.197-206
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• 2007

P2X receptors are membrane-bound ion channels that conduct $Na^+,\;K^+$, and $Ca^{2+}$ in response to ATP and its analogs. There are seven subunits identified so far ($P2X_1-P2X_7$). $P2X_2$ receptors are known to be expressed in a wide range of organs including brains and adrenal grands. PC12 cells are originated from adrenal grand and differentiated by nerve growth factor or pituitary adenylate cyclase activating poly peptide (PACAP). Previous studies indicate that $P2X_2$ receptor activation in PC12 cells couples to $Ca^{2+}-dependent$ release of catecholamine and ATP. It is known that acidic pH potentiates ATP currents at $P2X_2$ receptors. This leads to a hypothesis that $P2X_2$ receptors may play an important role in PC12 cell differentiation, one of the characteristics of which is neurite outgrowth, induced by the hormones under lower pH. In the present study, we isolated several clones which potentiate neurite outgrowth by PACAP in acidic pH (6.8), but not in alkaline pH (7.6). RT-PCR and electrophysiology data indicate that these clones express only functional $P2X_2$ receptors in the absence or presence of PACAP for 3 days. Potentiation of neurite outgrowth resulted from PACAP (100 nM) in acidic pH is inhibited by the two P2X receptor antagonists, suramin and PPADS ($100\;{\mu}M)$ each), and exogenous exprerssion of ATP-binding mutant $P2X_2$ receptor subunit ($P2X_2[K69A]$). However, acid sensing ion channels (ASICs) are not involved in PACAP-induced neurite outgrowth potentiation in lower pH since treatments of an inhibitor of ASICs, amyloride ($10\;{\mu}M$), did not give any effects to neurite extension. The vesicular proton pump ($H^+-ATPase$) inhibitor, bafilomycin (100 nM), reduced neurite extension indicating that ATP release resulted from $P2X_2$ receptor activation in PC12 cells is needed for neurite outgrowth. These were confirmed by activation of mitogen activated protein kinases, such as ERKs and p38. These results suggest roles of ATP and $P2X_2$ receptors in hormone-induced cell differentiation or neuronal synaptogenesis in local acidic environments.

• BMB Reports
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• 제40권6호
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• pp.888-894
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• 2007

Src homology (SH) domains of phospholipase C-$\gamma1$ (PLC-$\gamma1$) impair NGF-mediated PC12 cells differentiation. However, whether the enzymatic activity is also implicated in this process remains elusive. Here, we report that the enzymatic activity of phospholipase C-$\gamma1$ (PLC-$\gamma1$) is at least partially involved to the blockage of neuronal differentiation via an abrogation of MAPK activation, as well as sustained Akt activation. By contrast, Overexpression of WT-PLC-$\gamma1$ exhibited sustained NGF-induced MAPK activation, and triggered transient Akt activation resulting in profound inhibition of neurite outgrowth. However, lipase-inactive mutant (LIM) PLC-$\gamma1$ cells fail to suppress neurite outgrowth, although it contains intact SH domains, specifically enhancing the expression of cyclin D1 and p21 proteins, which regulate the function of retinoblastoma Rb protein. These observations show that the lipase inactive mutant of PLC-$\gamma1$ does not alter NGF-induced neuronal differentiation via enzymatic inability and the modulation of cell cycle regulatory proteins independent on SH3 domain.