• Journal of Life Science
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• v.20 no.7
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• pp.969-976
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• 2010

In vivo studies of KR-31125 (2-butyl-5-dimethoxymethyl-6-phenyl-7-methyl-3-[[2'-(1H-tetrazol-5-yl) biphenyl-4-yl]methyl]-3H-imidazo[4,5-b]pyridine) were performed in pithed rats, conscious angiotensin II (AII) challenged normotensive rats, renal hypertensive rats (RHRs) and furosemide-treated beagle dogs. KR-31125 induced a non-parallel right shift in the dose-pressor response curve to AII ($ID_{50}$: 0.095 mg/kg) with a dose-dependent reduction in the maximum responses in pithed rats. Compared to losartan, this antagonistic effect was about 18 times more potent, presenting competitive antagonism. Other agonists such as norepinephrine and vasopressin did not alter the responses induced by KR-31125. Orally administered KR-31125 had no agonistic effect and dose-dependently inhibited the pressor response to AII with a slightly weaker potency ($ID_{50}$: 0.25 and 0.47 mg/kg, respectively) in the AII-challenged normotensive rat model, but with a more rapid onset of action than losartan (time to $E_{max}$: 30 min for KR-31125 and 6 hr for losartan). KR-31125 produced a dose-dependent antihypertensive effect with a higher potency than losartan in RHRs, and these effects were confirmed in furosemide-treated dogs where they presented a dose-dependent and long-lasting (>8 hr) antihypertensive effect with a rapid onset of action (time to $E_{max}$: 2-4 hr), as well as a 20-fold greater potency than losartan. These results suggest that KR-31125 is a potent, orally active $AT_1$ receptor antagonist that can be applied to the development of new diagnostic and research tools as an added exploratory potential of $AT_1$ receptor antagonist.

• Molecules and Cells
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• v.41 no.6
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• pp.553-561
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• 2018

Icariside II (ICA II) is used in erectile dysfunction treatment. Adipose tissue-derived stem cells (ADSCs) are efficient at improving erectile function. This study aimed to explore the action mechanism of ADSCs in improving erectile function. ADSCs were isolated from the adipose tissues of rats. Cell proliferation was determined using the Cell Counting Kit-8 (CCK-8) assay. The expressions of mRNA and protein were determined separately through qRT-PCR and western blot. The endogenous expressions of related genes were regulated using recombinant plasmids and cell transfection. A Dual-Luciferase Reporter Assay was performed to determine the interaction between miR-34a and STAT3. Rat models with bilateral cavernous nerve injuries (BCNIs) were used to assess erectile function through the detection of mean arterial pressure (MAP) and intracavernosal pressure (ICP). ICA II promoted ADSCs' proliferation and differentiation to Schwann cells (SCs) through the inhibition of miR-34a. Suppressed miR-34a promoted the differentiation of ADSCs to SCs by upregulating STAT3. ICA II promoted the differentiation of ADSCs to SCs through the miR-34a/STAT3 pathway. The combination of ICA II and ADSCs preserved the erectile function of the BCNI model rats. ADSCs treated with ICA II markedly preserved the erectile function of the BCNI model rats, which was reversed through miR-34a overexpression. ICA II promotes the differentiation of ADSCs to SCs through the miR34a/STAT3 pathway, contributing to erectile function preservation after the occurrence of a cavernous nerve injury.

• The Korean Journal of Physiology
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• v.29 no.1
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• pp.13-27
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• 1995

single $K^{+}$ channels of skeletal muscle from the rat and frog were into planar lipid bilayers and their properties were studied. Fusion was induced by an osmotic gradient. Of the four types of $K^{+}$ channels recorded, the two most frequently observed were a voltage and $Ca^{2+}-activated$ $K^{+}$ channel and a $K^{+}$ channel with a prominent conductance substate. The first $K^{+}$ channel was identified as the large $Ca^{2+}-activated$ $K^{+}$ (BK) channel because the open-state probability was increased with depolarization (e-fold change per $10.6{\pm}3.5$ mV, n=8) and internal $Ca^{2+}$ (half-activation at $16.7{\pm}3.8$ mV, n=8, pCa 4) and its conductance was large ($247{\pm}4.9$ pS, n=24 in 0.1 M KCI). Lifetime distributions of open- and closed-states could be fitted with single exponentials of several milliseconds. The mean open- and closed-lifetimes were linearly dependent on the intracellular $[Ca^{2+}]$ and $1/[Ca^{2+}]$, respectively. The second $K^{+}$ channel showed a conductance substate at $30{\sim}60%$ of the open state. Its current-voltage relation was linear in the range of $-80\;{\sim}\;+80\;mV$. The slope conductance of the substate and open-state were 40 and 144 pS in 0.2 M KCl, respectively. The channel was highly selective for $K^{+}$ over Cl. The open-state probability was weakly voltage-dependent (e-fold change per 35 mV. The lifetime distributions of open- and closed-states were fitted with two exponentials and the major gating occurred slowly at several hundred milliseconds. Based on the above results, we think the second type of $K^{+}$ channel is the sarcoplasmic reticulum $K^{+}$ (SRK) channel. In addition, both types of channel were also incorporated into the lipids extracted from the skeletal muscle. The channel properties recorded in the bilayers termed from synthetic and extracted lipids were qualitatively similar. Our data indicate that BK and SRK channels are rich in the skeletal muscle and their properties and regulation could be effectively studied in planar lipid bilayer.

• Journal of Pharmacopuncture
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• v.3 no.2
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• pp.169-189
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• 2000

To investigate effects of vanous herbal-acupuncture, which were Daebangpungtang, Oyaksungisan, Dokhwalgisaengtang, and Binsosan on Adjuvant Arthritis in rats, the edema rate, the number of WBC, the quantity of TNF-${\alpa}$, COX -2, and IL-6, and histological test of the muscular tissue were measured in the arthritis part. After elicilating arthritis of Sprague Dawely(SD) rats by injection of Freund's complets adjuvant for 2 weeks, saline was injected for the control group, Daebangpungtang acua-acupuncture was injected for the Daebangpungtang group, Oyaksungisan acua-acupuncture was injected for the Oyaksungisan group, Dokhwalgisaengtang acua-acupuncture was injected for the Dokhwalgisaengtang group, and Binsosan acua-acupuncture was injected for the Binsosan group during 30days. Selected point was ST35 in all groups. 1. The number of WBC was $8.24{\pm}0.51$($10^3$/ml) in the normal group and $27.35{\pm}3.51$($10^3$/ml) in the control group. the Daebangpungtang group and the Oyaksungisan group decreased each $20.42{\pm}2.75$($10^3$/ml) and $19.78{\pm}4.99$($10^3$/ml) in the Exp.ll group. This fact showed that the group Exp.ll was more effective than the control group effectively. (P<0.05) 2. The volume of the paw were checked. The volume of paw was $0.62{\pm}0.11mm in the control group and $0.45{\pm}0.08$mm in the Daebangpungtang group and $0.47{\pm}0.07$mm in the Oyaksungisan group, the swelling of the paw was restricted significantly in the Daebangpungtang and Oyaksungisan group(P<0.05) 3. The bands of the TNF-${\alpa}$, COX -2 in the muscular tissue of the control group wcre certain and thick than other groups(except normal group), and the band of the IL-6 in the muscular tissue of all group(except normal group) were similar forms. 4. In histological finding, because of severe inflammatory reaction, remarkably irregular tissue and large amount of inflammatory cells were found in thc control and Dokhwalgisaengtang group. But the Oyaksungisan and Daebangpul1gtang group showed small amount of inflammatory cells, the refrained inflammatory state and even recovering state. From these results, it is showed Oyaksugisan and Daebangpungtang acua-acupuncturc refrain inflammatory reaction and muscular tissue necrosis in SD rats paw were induced by Freund's complete adjuvant

• Journal of Pharmacopuncture
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• v.3 no.2
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• pp.191-212
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• 2000

Objective: This study was perfomled to examine the therapeutic effect of aqua-acupuncture solution of Hominis Placenta(HP) on kidney and liver intoxicated by $HgCI_2$ in rats. Methods: $10\%$ and $25\%$ HP aqua-acupuncture were carried out everyday for 8 days on corresponding bilateral loci of Shinsu(BL23) and Kansu(BL18), respectively, after mercuric chloride intoxication in rats. Thereafter BUN, creatinine, GOT, GPT, ALP, ${\gamma}$-GT, albumin and total bilirubin were measured before intoxication, and at the 4th and the 8th experimental day. Histopathological and immunochemical observation were also carried out. Results: 1. It showed significant decreases of BUN in the group of $10\%$ HP aqua-acupuncture into Shinsu on the 4th experimental day as compared with the control group. 2. It showed significant decreases of creatinine in the group of $10\%$ HP aqua-acupuncture into Shinsu on the 4th and the 8th experimental days as compared with the control group. 3. There were not any significant changes of GOT, GPT, ALP,${\gamma}$-GT, albumin and total bilirubin in the HP aqua-acupuncture groups compared with the control group. 4. By the histopathological observations on kidney under a light microscope, alt the $10\%$ and $25\%$ HP aqua-acupuncture into Shinsu showed the preventive effect on tubulo-interstitial necrosis and muItifocal calcification in tubular lumen respectively compared with the control group. 5. By the histopathological observations on liver under a light mIcroscope, the groups $10\%$ and $25\%$ HP aqua--acupuncture into Kansu did not show any significant changes in the liver compared with the control group. 6. By the immunochemical analysis of heat shock protein(hsp) and glucose-regulated protein(grp) in rat renal cortex, the expressions of hsp70 and grp78 were decreased in the $10\%$ and $25\%$ HP aqua-acupuncture into Shinsu respectively compared with the control group. Conclusion: These results suggest that Hominis Placenta aqua-acupuncture have an effect on prevention and protection of renal intoxication by $HgCI_2$ in rats.

• Physical Therapy Korea
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• v.14 no.3
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• pp.48-56
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• 2007

Environmental Enrichment (EE) alone is not capable of enhancing the fine digit and the forelimb functions. Therefore, we applied modified constraint-induced movement therapy (mCIMT) under the influence of EE to assess its effect on promoting improved forelimb sensorimotor functions. Focal ischemic brain injury was produced in Sprague-Dawley rats (60 rats, $250{\pm}50$ g) through middle cerebral artery occlusion (MCAO). Before MCAO induction, all rats were trained in modified limb placing tests and reaching tasks for 1 week. Then they were randomly divided into three groups: Group I: application of standard environment (SE) after MCAO induction (n=20), Group II: application of EE after MCAO induction (n=20), Group III: MCAO+EE, mCIMT and task-oriented training that was initiated at 10th day after MCAO induction (n=20). We also applied mCIMT (between 9 AM and 5 PM/daily) which included restraining the forelimb ipsilateral to the lesion using the 'Jones & Schallert' method. We assessed the change of modified limb placing, single pellet reaching test and the immunoreactivity of BDNF by immunohistochemistry (pre, 1st, 5th, 10th and 20th day). Group I showed no improved outcome, whereas group II and III significantly improved on the use of the forelimb and the immunoreactivity. The qualitative analysis of the skilled reaching test, of group III showed the greatest improvement in the fine digit and the forelimb function. These results suggest that EE combined with mCIMT is more functional in promoting enhanced fine digit and forelimb functional movements.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.814-820
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• 2005

This study was designed to determine the effect of chitosan on in vivo lipid metabolism in male Sprague-Dawley rats treated with ethanol. Rats were divided into four groups and reared for 6 weeks: E group ($35\%$ of total calories from ethanol), EC I group ($ethanol+0.5\%$ of chitosan), EC II group ($ethanol +1\%$ of chitosan) and control group (dextrin as much as ethanol treated). The levels of serum total cholesterol (TC) and LDL-cholesterol (LDL-C), GOT and GPT in plasma, and triglyceride (TG) in liver were remarkably increased in the rats treated with ethanol. However, the treatment of $1\%$ chitosan significantly lowered those parameter levels. In particular the values of r-HDL (the ratio of HDL-C to TC) in the rats fed in combination with ethanol and chitosan were relatively higher than that of the E group. The increased lipid droplets were observed in the hepatocytes of the rats treated with ethanol, but chitosan treatment reduced in the number and the size of the lipid droplets. These results suggest that chitosan improve in vivo lipid metabolism and Potentially protect hepatotoxicity of the rat liver treated with ethanol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.843-847
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• 1995

To evaluate the effect of dietary fiber on the protein utilization, Sprague-Dawley rats were fed diet containing 15% or 30% of pectin and 15% or 30% ${\alpha}-cellulose$. Control group was fed fiber free diet. The animals were fed and libitum for 5 weeks. Weight gain was less in the rat fed a pectin supplemented diet than those fed ${\alpha}-cellulose$ supplemented or control diet. Furthermore, weight gain decreased more by the addition of 30% pectin than 15% pectin level. The rats fed ${\alpha}-cellulose$ or pectin shwoed a decreasing tendency of food efficiency ratio compared to the control group. The rats fed a diet containing pectin showed an increasing tendency of the liver weight compared to the control group and those fed cellulose. The rats fed a diet containing pectin showed a decreasing tendency of hepatic protein content compared to those fed cellulose or control group fed fiber free diet. The rats fed diet containing pectin(15%, 30%) showed remarkable decreased activity of liver xanthine oxidase compared with those fed ${\alpha}-cellulose$ or the control group. These results suggested that the pectin may be alter the absorption of protein in intestinal lumen.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.859-866
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• 1995

This study was done to investigate the effects of chronic ethanol feeding on hepatic microsomal cytochrome system, lipid peroxidation and peroxide metabolizing enzyme activities in 2-acetylaminofluorene(2-AAF) treated rats. Male Sprague-Dawley rats, weighing 120~125g, were pair-fed liquid diets containing 35% of total calories either as ethanol or isocaloric carbohydrates for 6 weeks. After 4 weeks of experimental diet feeding, 2-AAF(100mg/kg body weight) was injected twice a week intraperitoneally. Both weight and percent liver weight per body weight were significantly changed by ethanol feeding. Hepatic microsomal lipid peroxide value and the activities of glutathione(GSH) peroxidase and GSH reductase were not changed by either ethanol or 2-AAF treatment. However the analysis of cytochrome systems showed that both ethanol and 2-AAF increased cytochrome P-450 and bs contents although cytochrome P-450 content was moe affected by 2-AAF while cytochrome b5 content by ethanol. Cytosolic GSH S-transferase activity, which is often elevated during chemical carcinogenesis, also significantly increased by either ethanol feeding or 2-AAF treatment. Overall values for the cytochrome contents and GSH S-transferase activities were highest in 2-AAF treated rats fed ethanol. These results might support the hypothesis that the increase in liver cancer risk associated with chronic ethanol consumption might be due to, at least in part, enhancement of carcinogen bioactivation by ethanol.

• Journal of Environmental Health Sciences
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• v.39 no.1
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• pp.48-55
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• 2013

Objective: The use of nanoparticle products is expected to present a potential harmful effect on consumers. Also, the lack of information regarding inhaled nanoparticles may pose a serious problem. In this study, we addressed this issue by studying pulmonary toxicity after nasal instillation of Al-NPs in SD rats. Methods: The animals were exposed to Al-NPs at 1 mg/kg body weight (low dose), 20 mg/kg body weight (medium dose) and 40 mg/kg body weight (high dose). To determine pulmonary toxicity, bronchoalveolar lavage (ts.AnBAL) fluid analysis and histopathological examination were conducted in rats. In addition, cell viability was investigated at 24 hours after the treatment with Al-NPs. Results: BAL fluid analysis showed that total cells (TC) count and total protein (TP) concentrations increased significantly in all treatment groups, approximately two to three times. Also, lactate dehydrogenase (LDH) and cytokines such as TNF-alpha and IL-6 dose-dependently increased following nasal instillation of Al-NPs. However, polymorphonuclear leukocytes (PMNs) levels showed no significant changes in a dose dependant manner in BAL fluid. In the cytotoxicity analysis, the treatment of Al-NPs significantly and dose-dependently induced cell viability loss (20 to 30%) and damage of cell membrane (5 to 10%) in rat normal lung epithelial cells (L2). Conclusions: Our results suggest that inhaled Al-NPs in the lungs may be removed quickly by alveolar macrophages with minimal inflammatory reaction, but Al-NPs have the potential to affect lung permeability. Therefore, extensive toxicity evaluations of Al-NPs are required prior to their practical application as consumer products.