• Tuberculosis and Respiratory Diseases
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• 제44권2호
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• pp.338-348
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• 1997

Background : Endotoxin, the component of outermembrane of gram negative organism, plays an important role in the initiation and amplification of inflammatory reaction by its effects on inflammatory cells. Until recently, there have been continuing efforts to delinate the mechanisms of the signal trasduction pathway of endotoxin stimuli on inflammatory cells. By uncovering the mechanisms of signal transduction pathway of endotoxin stimuli, we can expect to have tools to control the excessive inflammatory responses which sometimes may be fatal to the involved host. It was generally accepted that endotoxin exerts its inflammatory effects through inflammatory cytokines that are produced by endotoxin-stimulated inflammatory cells and there were some reports on the importance of protein kinase C and protein tyrosine kinase activation in the production of inflammatory cytokines by endotoxin So we evaluated the effect of pretreatment of protein kinase C inhibitors (H7, Staurosporin) and protein tyrosine kinase inhibitors(Herbimycin, Genistein) on the endotoxin-stimulated cytokines(IL-8 & TNF-$\alpha$) mRNA expression. Method : Peripheral blood monocytes were isolated from healthy volunteers by Ficoll-Hypaque density gradient method and purified by adhesion to 60mm Petri dishes. Endotoxin(LPS 100ng/ml) was added to each dishes except one control dish, and each endotoxin-stimulated dishes was preincubated with H7, Staurosporin(protein kinase C inhibitor), Herbimycin or Genistein(protein tyrosine kinase inhibitor) respectively except one dish. Four hours later the endotoxin stimulation, total RNA was extracted and Northern blot analysis for IL-8 mRNA and TNF-$\alpha$ mRNA was done. Result : Endotoxin stimulation increased the expression of IL-8 mRNA and TNF-$\alpha$ mRNA expression in human peripheral blood monocyte as expected and the stimulatory effect of endotoxin on TNF-$\alpha$ mRNA expression was inhibited by protein kinase C inhibitors(H7, Staurosporin) and protein tyrosine kinase inhibitors (Herbimycin, Genistein). The inhibitory effect of each drugs was increased with increasing concentration. The stimulatory effect of endotoxin on IL-8 mRNA was also inhibited by H7 and protein tyrosine kinase inhibitors (Herbimycin, Genistein) dose-dependently but not by Staurosporin. Conclusion : Protein kinase C and protein tyrosine kinase are involved in the endotoxin induced signal transduction pathway in human peripheral blood monocyte.

• BMB Reports
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• 제30권2호
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• pp.89-94
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• 1997

In this study, during the activation of neutrophil responses by sodium fluoride. involvement of protein tyrosine kinase was studied. Respiratory burst lysosomal enzyme release and elevation of $[Ca^{2+}]_i$stimulated by sodium fluoride in neutrophils were inhibited by protein kinase inhibitors, genistein and tyrphostin. The inhibitory effect of genistein and tyrphostin on superoxide and $H_{2}O_{2}$ production was less than that of protein kinase C inhibitors, staurosporine and H-7. Staurosporine and H-7 had little or no effect on the release of myeloperoxidase and acid phosphatase stimulated by sodium fluoride. EGTA and verapamil inhibited the elevation of $[Ca^{2+}]_i$ evoked by sodium fluoride. The inhibitory effect of staurosporine on the elevation of $[Ca^{2+}]_i$ was less than that of genistein. Phorbol 12-myristate 13-acetate (PMA)-stimulated superoxide production, which is sensitive to staurosporine, was further enhanced by genistein, whereas the stimulatory action of PMA on myeloperoxidase release was inhibited by genistein. A pretreatment of neutrophils with PMA signifcantly attenuated sodium fluoride-evoked elevation of $[Ca^{2+}]_i$ These results suggest that protein tyrosine kinase may be involved in the activation process of neutrophil responses due to direct stimulation of guanine nucleotide regulatory proteins. In neutrophil responses, PMA-stimulated neutrophils appear to show a different type of inhibition of protein tyrosine kinase.

• 대한약리학회지
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• 제32권1호
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• pp.103-112
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• 1996

Platelet-activating factor (PAF)에 의하여 자극된 호중구 respiratory burst, 탈과립과 세포질 칼슘농도의 증가에 있어 protein kinase C와 protein tyrosine kinase의 역할을 관찰하였다. PAF에 의하여 자극된 호중구에서 superoxide 및 $H_2O_2$의 생성과 myeloperoxidase와 acid phosphatase의 유리는 protein kinase C 억제제인 staurosporine과 H-7 그리고 protein tyrosine kinase 억제제인 genistein과 tyrphostin에 의하여 억제되었다. PAF에 의한 호중구 세포내 칼슘농도의 증가는 staurosporine, genistein과 methyl-2,5-dihydroxycinnamate에 의하여 억제 되었다. Staurosporine은 PAF에 의하여 자극된 호중구에서 세포내 칼슘유리와 망간유입을 억제 하였다. Genistein과 methyl-2,5-dihydroxycinnamate는 PAF에 의한 망간유입을 억제하였으나, 세포내 칼슘유리에 대한 이들의 효과는 관찰되지 않았다. PMA에 의하여 활성화된 호중구에서 세포내 칼슘농도의 증가에 대한 PAF의 자극효과는 감소되었다. Protein kinase C와 protein tyrosine kinase는 PAF에 의하여 자극된 호중구에서의 respiratory burst, lysosomal enzyme유리와 칼슘동원에 관여할 것으로 제시된다. 세포내 칼슘농도의 증가는 protein kinase의 영향을 다르게 받는 세포내 칼슘유리와 세포외부로 부터의 칼슘유입에 의하여 이루어질 것으로 추정된다. Protein kinase C가 활성화되어 있는 상태에서 세포내 칼슘동원에 대한 PAF의 자극작용은 감소될 것으로 시사된다.

• 대한약리학회지
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• 제32권3호
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• pp.417-424
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• 1996

본 연구는 C5a에 의해 자극된 호중구에서 세포내 칼슘유리와 세포외부로부터 칼슘유입에 있어 protein kinase C와 protein tyrosine kinase의 관여 여부를 조사하였다. Protein kinase C 억제제인 staurosporine과 H-7은 C5a에 의해 자극된 호중구에서 세포내 칼슘유리를 억제하였으나, 세포막을 교차한 칼슘유입이나 세포내 칼슘농도 증가에 영향을 나타내지 않았다. C5a에 의한 세포내 칼슘유리와 칼슘유입은 protein tyrosine kinase 억제제인 genistein과 methyl-2,5-dihydroxycinnamate에 의해서 억제 되었다. ADP에 의해 야기된 세포내 칼슘농도의 증가는 genistein과 methyl-2,5-dihydroxycinnamate에 의해서 억제되었으나 staurosporine과 H-7의 영향은 받지 않았다. Genistein과 methyl-2,5-dihydroxy-cinnamate는 thapsigargin을 처리한 호중구에서 칼슘유입을 감소시켰으나 이에 대한 staurosporine 과 H-7의 효과는 나타나지 않았다. 호중구를 phorbol 12-myristate 13-acetate로 전처치하였을때 세포내 칼슘증가에 미치는 C5a의 자극 효과는 감소하였다. 이상의 결과로 부터 protein tyrosine kinase는 C5a에 의해 활성화된 호중구에서 세포내 칼슘유리와 세포막을 교차한 칼슘유입의 조절에 관여할 것으로 추정된다.

• Archives of Pharmacal Research
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• 제16권2호
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• pp.114-117
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• 1993

Ginsenosides present in the roots of panax ginseng C.A. Meyer were shown to induce a stimulatory effect on the overexpressed cellular chicken c-src protein tyrossine kinase in NH3T3 cells. Among 4 ginsenosides studied $(G-Rb_2,\;G-Rc,\;G-Re\;and\;G-Rg_1),\;G-Rg_1$ showed the most stimulatory effect at $16.7\mu{g/ml}$ ginsenoside concentration increasing the activity by 2-4 times. Inhibitors of either protein synthesis or RNA synthesis blocked the activation of c-src proein tyrosine kinase. These results suggest that the csrc kinase activation apprars to involve an increase in the amount of protein of the kinase by transcriptional control mechanism rather than an increase in the kinase activity.

• 대한의생명과학회지
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• 제2권2호
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• pp.175-185
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• 1996

모든 진핵세포에 존재하며 세포의 성장 및 분화에 주로 관계되는 신호전달물질의 하나인 Mitogen-activated protein(MAP)kinase의 mitogen에 의한 핵내 활성화와 기질 인산화에 대해 알아보기 위해 본 실험을 수행하였다. P388세포를 10% fetal bovine serum이 첨가된 DMEM배지에 배양한 후, 혈청이 들어있지 않은 배지에서 24시간 더 배양하고 serum 및 PMA를 농도별로 처리하여 세포성 장을 위한 최적 농도를 확인한 결과 serum은 5-20% 농도에서 세포성장을 촉진시켰고 PMA는 실험한 모든 농도에서 세포성장을 거의 촉진시키지 못하는 경향을 확인하였다. 이어 P388 세포를 serum 및 PMA로 10 분간 활성화하여 파쇄한후 세포질분획과 핵분획으로 분리하여 각 분획을 10% gel 상에서 전기영동 하여 nitrocellulose paper에 옳긴 후 anti-ERKI antibody를 이용해 확인해본 결과 serum, PMA로 처리된 세포 모두에서 MAP kinase의 핵내 이동이 관찰되었으며 특히 세포질 내에 주로 존재하는 42, 44 Kd의 MAP kinase isoform중 42 Kd의 isoform이 주로 핵내로 이동되는 것이 관찰되었다. MAP kinase의 기질인산화 실험을 위해 serum으로 활성화시킨 세포를 파쇄하여 SP-sephadex C-50, Phenyl superose, Mono Q column의 순서로 chromatography를 시 행하여 MAP kinase를 부분분리 하였다. 이와 같이 얻은 MAP kinase를 가지고 면역 T세포에 존재하는 tyrosine kinase인 $p56^{lck}$ 의 N-terminal peptide로 구성된 GST-fusion protein에 대한 인산화를 확인하였다. 또한 세포에서 분리한 MAP kinase를 가지고 transcription factor의 하나인 c-Jun protein에 대한 인산화실험을 실시한 결과 MAP kinase에 의해 인산화 됨이 확인되었다. 이상의 결과를 통해 P388세포는 (1)세포 성장시 외부 신호를 G-protein-coupled receptor/protein kinase C/MAP kinase의 경로보다는 주로 tyrosine kinase receptor protein/Ras/MAP kinase의 경로를 이용하여 핵으로 전달하는 것으로 추측되 며 (2) mitogen의 처리로 활성화된 MAP kinase중 주로 42 Kd isoform이 핵내로 이동하고, 분리한 MAP kinase가 GST-fusion protein과 transcription factor인 c-Jun을 모두 인산화 시키는 결과로 보아 MAP kinase의 isoform에 따라 표적 compartment가 다르고 결과적으로 표적 기질에 차이가 있을지 모른다고 간접적으로 추론할 수 있다.

• Archives of Pharmacal Research
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• 제21권3호
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• pp.315-319
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• 1998

Gastric smooth muscle of cats was used to investigate the involvement of protein kinase in vanadate-induced contraction. Vanadate caused a contraction of cat gastric smooth muscle in a dose-dependent manner. Vanadate-induced contraction was totally inhibited by 2 mM EGTA and 1.5 mM $LACI_3$ and significantly inhibited by $10\mu$M verapamil and $1\mu$M nifedipine, suggesting that vanadate-induced contraction is dependent on the extracellular $Ca^{2+}$ concentration, and the influx of extracellular $Ca^{2+}$ was mediated through voltage-dependent $Ca^{2+}$ channel. Both protein kinase C inhibitor and tyrosine kinase inhibitor significantly inhibited the vanadate-induced contraction and the combined inhibitory effect of two protein kinase inhibitors was greater than that of each one. But calmodulin antagonists did not have any influence on the vanadate-induced contraction. On the other hand, both forskolin ($1\mu$M) and sodium nitroprusside ($1\mu$M) significantly inhibited vanadate-induced contraction. Therefore, these results suggest that both protein kinase C and tyrosino kinase are involved in the vanadate-induced contraction which required the influx of extracellular $Ca^{2+}$ in cat gastric smooth muscle, and that the contractile mechanism of vanadate may be different from that of agonist binding to its specific receptor.

• The Korean Journal of Physiology and Pharmacology
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• 제8권2호
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• pp.111-115
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• 2004

Roundabout (Robo) is the transmembrane receptor for slit, the neuronal guidance molecule. In this study, the tyrosine phosphorylation of Robo was observed in Robo-transfected human embryonic kidney cells and developing rat brains, and found to be increased by the treatment with protein kinase A activator, forskolin. In contrast, protein kinase C activation by phorbol-12-myristate-13-acetate decreased the phosphorylation of Robo. Intracellular calcium was required for the tyrosine phosphorylation. Furthermore, the transfection of an Eph receptor tyrosine kinase dramatically enhanced the tyrosine phosphorylation. These findings indicate that the tyrosine phosphorylation of Robo is regulated by multiple mechanisms, and that Eph receptor kinases may play a role in the regulation of tyrosine phosphorylation of Robo in the rat brain.

• 약학회지
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• 제45권3호
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• pp.287-292
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• 2001

To investigate whether phospholipase $A_2$pathway is involved in histamine release of rat peritoneal mast cells, we measured histamine release in the presence of various enzyme inhibitors involved in eicosanoid pathway, such as phospholipase $A_2$, cyclooxygenase and lipoxygenase. Phospholipase $A_2$inhibitors, manoalide and OPC, significantly inhibited histamine release induced by 100 $\mu$M ATP and 1$\mu$g/ml compound 48/80. Cyclooxygenase inhibitors, ibuprofen and indomethacin, significantly inhibited ATP-induced histamine release and lipoxygenase inhibitors, baicalein and caffeic acid, also significantly inhibited. To investigate the involvement of protein kinase in ATP- and compound 48/80-induced histamine release, we observed effects of protein kinase inhibitors on histamine release. Bisindolmaleimide (protein kinase C antagonist) dose-dependently inhibited both ATP and compound 48/80-induced histamine release. Tyrosine kinase inhibitors (methyl 2,5-dihydroxy cinnamate and genistein) dose-dependently inhibited ATP and compound 48/80-induced histamine release. Protein kinase C and tyrosine kinase seem to be involved in histamine release induced by ATP and compound 48/80. These results suggest that phospholipase $A_2$pathway as well as protein kinase C and tyrosine kinase are involved in histamine release of rat peritoneal mast cells by ATP and compound 48/80.

• BMB Reports
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• 제34권1호
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• pp.33-38
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• 2001

The human PTK6 (also known as Brk) polypeptide, which is deduced from its full-length cDNA, represents a non-receptor protein tyrosine kinase (PTK). It contains SH3, SH2, and tyrosine kinase catalytic domains that are closely related to Src family members. We generated an antihuman PTK6 antibody by immunizing rabbits with a PTK6-specific oligopeptide conjugated to BSA, which corresponds to 11 amino acid residues near the C-terminus. An immunoblot analysis with the antibody detected an expected 52-kDa band in various mammalian transformed cell lines. Immunoprecipitation and immunoblot analyses demonstrated that PTK6 is phosphorylated on the tyrosine residues) and interacts with approximately a 23-kDa tyrosine-phosphorylated polypeptide (most likely a substrate of PTK6) in breast carcinoma T-47D cells. An immunofluorescence analysis demonstrated that PTK6 is localized throughout the cytoplasm of T-47D cells. These results support a possible role for PTK6 in the intracellular signal transduction through tyrosine phosphorylation.