• Bulletin of the Korean Chemical Society
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• 제34권10호
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• pp.3143-3146
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• 2013

• BMB Reports
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• 제40권2호
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• pp.180-188
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• 2007

In vivo studies have demonstrated that aldosterone is an independent contributor to glomerulosclerosis. In the present study, we have investigated whether aldosterone itself mediated glomerulosclerosis, as angiotensin II (Ang II) did, by inducing cultured renal mesangial cells to produce plasminogen activator inhibitor-1 (PAI-1), and whether these effects were mediated by aldosterone-induced increase in transforming growth factor $\beta_1$ (TGF-$\beta_1$) expression and cellular reactive oxygen species (ROS) activity. Quiescent rat mesangial cells were treated by aldosterone alone or by combination of aldosterone and spironolactone, Ang II, neutralizing antibody to TGF-$\beta_1$ or antioxidant Nacetylcysteme (NAC). This study indicate that aldosterone can increase PAI-1 mRNA and protein expression by cultured mesangial cells alone, which is independent of aldosterone-induced increases in TGF-$\beta_1$ expression and cellular ROS. The effects on PAI-1, TGF-$\beta_1$ and ROS generation were markedly attenuated by spironolactone, a mineralocorticoid receptor antagonist, which demonstrate that mineralocorticoid receptor (MR) may play a role in mediating these effects of aldosterone.

• BMB Reports
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• 제30권6호
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• pp.415-420
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• 1997

Although $CD4^+$ T cell responses to protein-derived antigen have well been understood, the epitopes recognized by hapten-specific $CD4^+$ T cells have not been fully defined. In this study, we characterized the response of a T cell hybridoma (5Di0.1B8) which is specific for a hapten. N-hydroxysuccinimidyl-4-azidobenzoate (HSAB) restricted by MHC class II $I-A^d$. Using three different antigen presenting cells (APCs) expressing $I-A^d$, the role of class II MHC proteins in haptenic antigen presentation and subsequent activation of 5D10.1B8 has been examined. Activation of 5D10.1B8 T cells by HSAB analogs was also performed. Our results show that each APC activated T cells differentially and that interleukin-2 (IL-2) augmented antigen-presenting ability of all the APCs, suggesting that increased expression of class II MHC protein by IL-2 played an important role in HSAB presentation and T cell activation. Finally, early T cell receptor-dependent signals induced by HSAB or its analogs were examined by phosphotyrosine immunoblot analysis, and showed that tyrosine phosphorylation level of a 18-20 kD protein increased upon stimulation.

• The Korean Journal of Physiology and Pharmacology
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• 제2권6호
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• pp.771-778
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• 1998

To investigate interaction of angiotensin converting enzyme (ACE) inhibitor with local tissue renin- angiotensin system (RAS), changes in gene expression of the RAS components in various tissues in response to chronic administration of an ACE inhibitor, enalapril, were examined in Sprague-Dawley male rats. Enalapril was administered in their drinking water $(3{\sim}4\;mg/day)$ over 8 wk. Plasma and renal ACE activity increased significantly after 4 and 8 wk of enalapril treatment. Renin levels of the plasma and kidney of the enalapril-treated rats markedly increased after 4 wk and decreased thereafter, but still remained significantly higher than those of control rats. Kidney mRNA levels of renin markedly increased after 4 and 8 wk of enalapril treatment, but those of angiotensinogen and ANG II-receptor subtypes, $AT_{1A}$ and $AT_{1B}$, did not change significantly. The liver expressed genes for renin, angiotensinogen and $AT_{1A}$ receptor subtype, but $AT_{1B}$ receptor subtype mRNA was not detectable by RT-PCR. None of mRNA for these RAS components in the liver changed significantly by enalapril treatment. The hypothalamus showed mRNA expressions of renin, angiotensinogen, $AT_{1A}$ and $AT_{1B}$ receptor subtypes. $AT_{1A}$ receptor subtype mRNA was more abundant than $AT_{1B}$ receptor subtype in the hypothalamus as shown in the kidney. However, gene expression of the RAS components remained unchanged during 8-wk treatment of enalapril. In the present study, chronic ACE inhibition increased plasma and renal levels of ACE and renin, but did not affect mRNA levels of other RAS components such as angiotensinogen, ANG II receptor subtypes in the kidney. Gene levels of the RAS components in the liver and hypothalamus were not altered by chronic treatment of enalapril. These results suggest the differential expression of the RAS components in response to enalapril, and localized action and some degree of tissue specificity of enalapril.

• Bulletin of the Korean Chemical Society
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• 제34권5호
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• pp.1543-1546
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• 2013

• 생약학회지
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• 제16권1호
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• pp.31-35
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• 1985

Intraperitoneal administration of ginseng butanol fraction(GBF) to chronic morphinization in male Sprague-Dawley rats inhibited the development of tolerance to the analgesic effect and hyperthermic action of morphine. Rats were rendered tolerant to morphine by subcutaneous multiple morphine injections for a period of 8 days. The development of tolerance was evidenced by the decreased analgesic response to morphine and inhibition of tolerance by the greater analgesic response. Concomitant administration of morphine with GBF blocked the tolerance to the hyperthermic effect of morphine as evidenced by elevation of body temperature by morphine. Dopamine receptor sensitivity was enhanced in morphine tolerant rats as measured by apomorphine induced in spontaneous motor activity. GBF administration also blocked dopamine receptor supersensitivity induced by chronic morphinization.

• The Journal of Korean Physical Therapy
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• 제19권4호
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• pp.33-41
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• 2007

Purpose: To investigate environmental enrichment and nerve stimulation follows in application times with the change of BDNF & Trk-B receptor in the motor cortex and spinal cord. Methods: Experimental groups were divided into the five groups. Group I: normal control group, Group II: experiment control group, Group III: sciatic never electrical stimulation after MCAO, Group IV: application of only environmental enrichment after MCAO, Group V: never electrical stimulation with environmental enrichment after MCAO. Histologic observation and coronal sections were processed individually in goat polyclonal antibody phosphorylated BDNF and rabbit polyclonal antibody Trk-B receptor. Results: In immunohistochemistric response of BDNF and Trk-B, group II were showed that lower response effect at postischemic 1 days, 3 days, and 7 days. Group V were showed that increase response effect at postischemic 3 days, 7 days and 14 days. Specially showed that the most response effect at postischemic 14 days. In neurobehavioral assessment, group V were significantly difference from other groups on between-subject effects. Conclusion: The above results suggest that combined environmental enrichment with peripheral nerve electrical stimulation in focal ischemic brain injury were more improved that the change of BDNF & Trk-B receptor expression than non treatment.

• Laboraroty Animal Research
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• 제34권4호
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• pp.140-146
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• 2018

Though bile acids have been well known as digestive juice, recent studies have demonstrated that bile acids bind to their endogenous receptors, including Farnesoid X receptor (FXR) and G protein-coupled bile acid receptor 1 (GPBAR1; TGR5) and serve as hormone to control various biological processes, including cholesterol/bile acid metabolism, glucose/lipid metabolism, immune responses, and energy metabolism. Deficiency of those bile acid receptors has been reported to induce diverse metabolic syndromes such as obesity, hyperlipidemia, hyperglycemia, and insulin resistance. As consistent, numerous studies have reported alteration of bile acid signaling pathways in type II diabetes patients. Interestingly, bile acids have shown to activate TGR5 in intestinal L cells and enhance secretion of glucagon-like peptide 1 (GLP-1) to potentiate insulin secretion in response to glucose. Moreover, FXR has been shown to crosstalk with TGR5 to control GLP-1 secretion. Altogether, bile acid receptors, FXR and TGR5 are potent therapeutic targets for the treatment of metabolic diseases, including type II diabetes.

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2002년도 국제심포지엄
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• pp.96-96
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• 2002

We examined the role of SR 144528 (N-[-(1S-endo-1,3,,3-trimethyl-bicycle[2, 2, 1 ] heptan-2-y1]-5-(-4-chloro-3-mothyl-phenyl)-(4-methylbenzyl)-pyrazole-3- carboxamide) in the modulation of certain AC isoforms in transiently transfected COS-7 cells. We found that CB2 in COS cells has a constitutive activity, and thus leading to inhibition of AC-V activity even in the absence of agonist. In addition, this constitutive modulation of AC is reversed by SR144528. It is now well established that several G protein-coupled receptors can signal without agonist stimulation(constitutive receptors). Inverse agonists have been shown to inhibit the activity of such constitutive G protein-coupled receptor signaling. Agonist activation of the G$\_$i/o/-coupled peripheral cannabinoid receptor CB2 normally inhibits adenylyl cyclase type V and stimulates adenylyl cyclase type II. Using transfected COS cells, we show here that application of SR144528, an inverse agonist of CB2, leads to a reverse action (stimulation of adenylyl cyclase V and inhibition of adenylyl cyclase II). This inverse agonism of SR144528 is dependent on the temperature, as well as on the concentration of the cDNA of CB2 transfected. Pertussis toxin blocked the regulation of adenylyl cyclase activity by SR 144528.

• Biomolecules & Therapeutics
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• 제3권1호
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• pp.21-27
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• 1995

The only compounds with antagonistic activity via AT$_1$receptor, one of two subtypes of angiotensin II (AII) receptor, have been demonstrated to block the vasoconstriction effects of AII and thereby provide therapeutic potential. This initiated the search for compounds with high specific affinity to AT$_1$receptor and their effective screening methods. The radioligand binding assay for the AII receptor is regarded as the primary method for the evaluation of AT$_1$receptor antagonists for their activity. In this paper, we characterized the liver AT$_1$receptor and describe the efficient method of the radioligand binding assay using rat liver as a source of AT$_1$receptor. Equilibrium binding studies with rat adrenal cortex, adrenal medulla, liver and bovine adrenal showed that the specific bindings of [$^3$H] AII were saturable in all tissues and the Scatchard plots of those data were linear, suggesting a single population of binding sites. Hill slopes were very near to the unity in all tissues. Kinetic studies of [$^3$H) AII binding in rat liver homogenates yielded two association rate constants, 4.10$\times$10$^{7}$ M$^{-1}$ min$^{-1}$ and 4.02$\times$10$^{9}$ M$^{-1}$ min$^{-1}$ , with a single dissociation rate constant, 7.07$\times$10$^{-3}$ min-$^{-1}$ , possibly due to the partial dissociation phenomenon. The rank order of inhibition potencies of [$^3$H] AII binding in rat liver was AII>Sarile>Losartan>PD 123177. Rat liver homogenates revealed to have very high density of homogeneous population of the AT$_1$receptor subtype, as the specifically bound [$^3$H] AII was not inhibited by PD 123177, the nonpeptide antagonist of AT$_2$. The results of this study demonstrated that the liver homogenates from rats could be the best receptor preparation for the AT$_1$receptor binding assay and provide an efficient system for the screening of newly synthesized candidate compounds of AT$_1$receptor antagonist.