• The Korean Journal of Pharmacology
• /
• v.26 no.2
• /
• pp.127-133
• /
• 1990

Dibutyryl-cyclic AMP (db-cAMP) and forskolin were used to investigate vasodilating mechanism of cAMP in rabbit aorta. Db-cAMP and forskolin inhibited the development of contractile tension induced by norepinephrine (NE) concentration-dependently. However, high $K{^+}-induced$ contractile tension was inhibited less effectively by db-cAMP and forskolin. Db-cAMP and forskolin inhibited $^{45}Ca^{2+}$ uptake increased by NE. Forskolin seemed to inhibit $^{45}Ca^{2+}$ uptake increased by high $K{^+}$, but this inhibition was not significant statistically. Db-cAMP inhibited $Ca^{2+}-transient$ contraction by NE in $Ca^{2+}-free$ solution. In conclusion, it seems that cAMP blocks $Ca^{2+}$ influx through receptor operated $Ca^{2+}$ channels (ROCs), but that the effect of cAMP on $Ca^{2+}$ influx through voltage gated $Ca^{2+}$ channels (VGCs) is not clear in this experiment. Furthermore, cAMP is likely to inhibit calcium release from the intracellular stores.

• Journal of Veterinary Clinics
• /
• v.30 no.6
• /
• pp.403-408
• /
• 2013

The objective of the present study is to detect the effect of ${\beta}$-glucan originated from Aureobasidium on the proliferation and collagen production in human dermal fibroblast cells with wound repopulation in vitro. The proliferative effects were assessed using a MTT assay as well as cell counts at 24 and 48 hr after treatment. Hydroxyproline was measured as an index of procollagen production with reverse-phase high pressure liquid chromatography. Oncostatin M was used as a reference agent. In glucagon treated group, dose-dependent and significant increase of optical density or fibroblast cell numbers was demonstrated, when compared with those of control from 0.1 mg/ml concentration. In addition, the numbers of cells which had migrated into the wound defects were more significantly and dose-dependently increased than those of non-treated control. However, no meaningful effects on the procollagen production were observed.

• Journal of Food Hygiene and Safety
• /
• v.30 no.3
• /
• pp.258-264
• /
• 2015

Withania somnifera has been used in folk medicine to treat various ailments for centuries. In this studies to investigate the whitening effect of Withania somnifera extracts as an active ingredient for whitening cosmetics, the antioxidant capacity and the effects of Withania somnifera extracts on melanogenesis in B16-F10 melanoma cells were identified. Withania somnifera extracts significantly reduced both tyrosinase activity and melanin content in a concentration-dependent manner. Furthermore, it was found that Withania somnifera extracts decreased ${\alpha}-MSH$ (melanocyte-stimulating hormone)-induced tyrosinase activity and MITF(microphthalmia associated transcription factor) protein expression. These data indicate that Withania somnifera extracts attenuate ${\alpha}$-MSH-stimulated melanin synthesis by modulating MITF expression and that they may be a useful therapeutic agent for treating hyperpigmentation and an ingredient of whitening cosmetics.

• Journal of fish pathology
• /
• v.9 no.1
• /
• pp.53-63
• /
• 1996

The present study was undertaken to investigate the physiological characteristics of the cholinergic responses in the tilapia dorsal aorta. In vessels under resting tension or precontracted with norepinephrine, acetylcholine caused only concentration-dependent vasoconstrictions. Contractile response to acetylcholine was not affected by the removal of endothelium or the application of methylene blue. Atropine, gallamine or pirenzepine shifted concentration-response curve to the right. However pirenzepine showed a similar effect on the curve only at high concentration ($1{\times}10^{-5}$M). Acetylcholine-induced vasoconstriction was not markedly influenced by indomethacin, or verapamil, but was almost abolished in the calcium-free physiological buffer solution. These results suggest that acetylcholine produces only an endothelium-independent vasoconstriction in tilapia dorsal aorta and that the contractile effect of acetylcholine is mainly mediated by the activation of $M_2$ subtype receptor, which might be associated with the extracellular calcium influx through receptor-linked calcium channel.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
• /
• v.7 no.1
• /
• pp.395-405
• /
• 2017

To confirm potential anti-cancer activities of ethylacetate (EtOAc) fraction from Orostachys japonicus on the A549 human lung cancer cells, this study examined. As a result of conducting MTS assay for measuring cell viability, the EtOAc fraction inhibited the proliferation of A549 cells in a dose-dependent manner. To investigate whether the inhibiting A549 cell viability was caused by apoptosis, this study analyzed chromatin condensation in A549 cells using DAPI staining. The morphological changes such as the formation of nuclear condensation were formed in a dose-dependent manner. Also, this study performed Annexin V-FITC staining for detecting phosphatidylinositol (PS). As a result of Annexin V-FITC staining to investigate level of early and late apoptosis, the apoptosis level treated with EtOAc fraction was higher than that of control. RT-PCR was performed to study the correlation between G2/M cell cycle arrest and cell cycle control genes. The anti-cancer activity of EtOAc fraction was accompanied by inhibition of CDK1, 4, cyclin B1 and D1 mRNA. This study also examined the expression of various marker proteins: p53, Bax, Bcl-2 and pro-caspase 3. Western blotting revealed that p53 and Bax proteins were up-regulated, and Bcl-2 and pro-caspase 3 proteins down-regulated in a time and dose-dependent manner.

• Journal of Life Science
• /
• v.17 no.7 s.87
• /
• pp.1019-1022
• /
• 2007

Thrombolytic therapy with tissue plasminogen activator (tPA) can improve the clinical outcome of ischemic stroke patients. However, its clinical application is limited by narrow therapeutic time windows and elevated risks of cerebral hemorrhage and brain injury. In part, these effects of tPA has been related to matrix metalloproteinase-9 (MMP-9) dysregulation. Here, we investigate that the effects of alteplase (tPA with short half-life) and pamiteplase (a modified tPA with long half-life) on the MMP-9 regulation in neurovascualr unit. The total levels of MMP-2 and MMP-9 in neuronal cells are lower than astrocytes. Alteplase (1-10 ${\mu}g/ml$) induced upregulation of MMP-2 and MMP-9 in rat cortical neurons and astrocytes, respectively. Whereas pamiteplase in a wide range of dose did not affect the MMP-2 and MMP-9 responses in both of cells. These results suggest that pamiteplase with long half-life can be provided as a agent that overcome the side effects of alteplase.

• The Korean Journal of Zoology
• /
• v.30 no.4
• /
• pp.341-350
• /
• 1987

LHRH분비와 환denylate cyclase활성에 미치는 PGE2, Opioid, 그리고 Ca2+의 영향을 흰쥐의 시상하부 조직을 사용하여 조사하였다. K+(30mM)에 의한 LHR광분비촉진은 Ca2+의존적인데 반하여, PGE2에 의해 촉진되는 LHR노 분비는 세포의 Ca2+농도에 의존하지 않았다. PGE2에 의한 LHR기 분비와 CAMP합성은 PGE2농도(1$\times$10-7M-1$\times$10-4M)에 비례하여 촉진되었으며, $\beta$-endorphin (1x10-3M)은 PGEa에 의한 LHRH 분비촉진과 CAMP합성을 공히 억제하였다. 오피오이드 수용체의 길항제인 Naloxone(Ix10-"M)은 $\beta$-endorphin에 의한 저해효과를 극복시켜서, LHR광 분비와 CAMP합성은 각각 회복되었으나, CAMP합성은 부분적인 회복을 보인 반면에, LHRH분비는 PGE2에 의한 촉진효과보다도 더 활성화되었다. 결론적으로 LHRH분비에 미치는 오퍼오이드의 억제작용은 PGE2-cAMP의 세포내 전달과정을 저해함으로써 유발되는것으로 추정 된다.정 된다.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.8
• /
• pp.1107-1113
• /
• 2016

The purpose of this study was to investigate the effects of catechu water extract on adipogenesis in 3T3-L1 adipocytes. 3T3-L1 preadipocytes were differentiated with adipogenic regents by incubation for 9 days in the absence or presence of catechu extract ranging from $1{\sim}200{\mu}g/mL$. The effect of catechu extracts on cell proliferation of 3T3-L1 preadipocytes was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The effect of catechu extracts on 3T3-L1 differentiation was examined by measuring intracellular lipid droplet and triglyceride contents. These results were obtained from preadipocyte proliferation and adipocyte differentiation of 3T3-L1. Catechu extracts inhibited lipid accumulation and remarkably decreased triglyceride contents in 3T3-L1 preadipocytes at a concentration showing no cytotoxicity. The anti-adipogenic effects of catechu appeared to be mediated by significant down-regulation of expression of peroxisome proliferator-activated receptor ${\gamma}$, CCAAT/enhancer-binding protein ${\alpha}$, and sterol regulatory element-binding protein 1c proteins apart from expression of hormone-sensitive lipase. We suggest that catechu extracts significantly inhibit adipogenesis and can be used for regulation of obesity.

• Korean Journal of Food Science and Technology
• /
• v.50 no.6
• /
• pp.671-679
• /
• 2018

Glasswort has attracted an attention because of its interesting physiological actions. In this study, the effects of glasswort on inflammatory events including nitric oxide (NO) synthesis and arachidonic acid metabolism in cultured RAW264.7 macrophages were investigated. A series of solvent fractions, including fractions of hexane (Fr.H), ethyl ether (Fr.E), ethyl acetate, butanol, and water, were prepared from a 70% methanol extract of glasswort. Among the fractions, Fr.E showed the strongest inhibition of NO synthesis and inducible NO synthase (iNOS) expression in lipopolysaccharide (LPS)-stimulated macrophages. At a concentration of $80{\mu}g/mL$, Fr.E decreased the NO and iNOS levels by 73 and 77%, respectively, after 24 h. Fr.E showed the most potent inhibitory effects on the expressions of cytosolic phospholipase $A_2$ and cyclooxygenase-2 with $IC_{50}$ values of 33.4 and $27.9{\mu}g/mL$, respectively. Fr.H and Fr.E also significantly inhibited 5-lipoxygenase expression in LPS-stimulated macrophages. These results suggest that the hydrophobic fractions of glasswort possess anti-inflammatory activities through modulating the arachidonic acid metabolism and NO synthesis.

• Korean Journal of Veterinary Research
• /
• v.38 no.3
• /
• pp.518-524
• /
• 1998

신장 근위세뇨관세포들은 사구체에서 여과된 물질의 재흡수, 분비 및 대사에 관여하는 여러 호르몬들의 수용체들을 가지고 있다. 이들중에서 dopamine(DA)과 angiotensin II(ANG II)가 $Na^{+}/H^{+}$ 상호운반계 조절에 중요한 역할을 하고 있다. 본 연구는 초대배양한 토끼 신장 근위세뇨관세포의 $Na^+$ uptake에 있어서 DA과 ANG II의 상호관계를 알아보고자 실시하였다. DA은 농도의존적으로 $Na^+$ uptake를 유의성 있게 억제하였다($10^{-6}M$ ; $83.2{\pm}7.2%$, $10^{-3}M$ ; $67.2{\pm}3.8%$ vs. control)(p<0.05). $DA_1$ 작동제(SKF 38393, $10^{-6}M$)는 대조군의 $81.4{\pm}6.7%$ 까지 $Na^+$ uptake를 유의성 있게 억제하였으나(p < 0.05) $DA_2$ 작동제는 영향을 미치지 않았다. $DA_1$ 길항제(SCH 23390, $10^{-6}M$)에 의해 DA의 $Na^+$ uptake 억제효과는 차단되었으나 $DA_2$ 길항제(spiperone, $10^{-6}M$)에 의해서는 영향을 받지 않았다. DA과 대조적으로 $10^{-11}M$ ANG II는 $AT_1$ 수용체를 통하여 대조군의 $120.7{\pm}4.9%$까지 $Na^+$ uptake를 유의성 있게 촉진하였다. (p < 0.05). DA 및 $10^{-11}M$ ANG II를 병합처리하였을 때 DA은 농도의존적으로 ANG II에 유도된 $Na^+$ uptake 촉진효과를 유의성 있게 차단하였다(p<0.05). 한편 ANG II에 의해 유도된 $Na^+$ uptake촉진작용은 $DA_1$ 또는 $DA_2$ 작동제에 의해 차단되었으나 DA에 의한 차단 효과는 $DA_1$ 및 $DA_2$ 길항제를 병합처리하였을 때만 반전되었다. 결론적으로 DA은 $DA_1$ 수용체를 통하여 $Na^+$ uptake를 억제하였으나 ANG II에 의한 $Na^+$ uptake 촉진작용의 억제에는 $DA_1$ 및 $DA_2$ 수용체 모두가 관여하였다.