• The Korean Journal of Physiology and Pharmacology
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• v.3 no.6
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• pp.605-613
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• 1999

The purpose of the present study was to evaluate cardiovascular regulation during passive standing (PS) after ethanol ingestion by spectral analysis of heart rate variability (HRV) in flushed and nonflushed subjects. Of 24 young male subjects, 8 belonged to flushed group (F) and 16 to nonflushed group (NF). Two sessions of 10-min PS were performed before and after ethanol (0.5 g/kg) ingestion. Powers of R-R interval variability in very low frequency $(VLF,\;0{\sim}0.05\;Hz),$ low frequency $(LF,\;0.05{\sim}0.15\;Hz)$ and high frequency $(HF,\;0.15{\sim}0.50\;Hz)$ bands, normalized powers (LFn and HFn) and LF/HF ratio were obtained. After ethanol ingestion, F showed higher heart rate than NF. PS increased LFn $(+22.9{\pm}3.6\;in\;NF,\;+12.8{\pm}4.7$ in F, in normalized units) and LF/HF $(+3.10{\pm}0.57\;in\;NF,\;+3.00{\pm}1.08\;in\;F)$ and decreased HFn powers. Ethanol ingestion increased LFn and LF/HF and decreased HFn. PS after ethanol resulted in higher LFn and LF/HF and lower HFn than the prior PS. F showed a greater and more sustained HRV change than NF after ethanol. In conclusion, PS or ethanol ingestion increased LFn and LF/HF and decreased HFn. Flushed subjects showed an accentuated HRV response to ethanol.

• CELLMED
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• v.5 no.1
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• pp.6.1-6.10
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• 2015

Fumaria indica Linn. (Syn: Fumaria parviflora, Fumariaceae) is a wildly grown weed, mentioned and recommended in classical Ayurvedic texts for treatments of variety of ailments including dermatological diseases, topical diseases, cardiovascular complaints, circulatory disease, fever and headache etc. The present pilot study was designed to experimentally verify the possibility that fumarates are the major bioactive principles of Fumaria indica extracts involved in their stress response modulating activities, and to estimate pharmacologicallyactive dose ranges of fumarates and standardized methanolic extract of Fumaria indica (MFI). Effect of single, 5 and 10 daily oral doses of pure fumaric acid (FA), monomethyl fumarate (MMF), dimethyl fumarate (DMF) and MFI was quantified in well validated rodent models viz. apomorphine induced cage climbing, stress induced hyperthermia, and elevated plus-maze tests. Obtained results reveal high efficacy of MFI and pure fumarates possess qualitatively analogous activity profiles in all the three tests. There were no significant difference in the potencies of pure FA, MMF and DMF in the three tests, whereas efficacy of MFI in the elevated plus maze test for anxiolytics was higher than in the other two tests. Efficacies of all the four test agents in all the three tests increased with increasing number of days of oral treatments. Results of these pilot experiments should be helpful for more rational selections of pharmacologically interesting dose ranges and treatment regimens of fumarates and Fumaria indica extracts for further more holistic explorations of their diverse therapeutic potentials.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.4
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• pp.383-391
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• 1999

This study was carried out to determine whether the effects of an ${\alpha}_2-adrenoceptor$ agonist, clonidine, on mean arterial pressure (MAP) and heart rate (HR) are influenced by mild hypothermia. Experiments were performed in respiration-controlled and spontaneously breathing pentobarbital-anesthetized rats. Rectal temperature was maintained at $37.5{\pm}0.3^{circ}C$ for normothermic groups or at $35.2{\pm}0.3^{circ}C$ for mild hypothermic groups. Intravenous injection of clonidine (1 and 2 ${\mu}g/kg)$ produced depressor and bradycardic responses in spontaneously breathing rats under both normothermic and mild hypothermic condition: a decrease in MAP was not altered but bradycardic response was significantly augmented in the mild hypothermic group as compared with the normothermic group. Under the respiration-controlled condition, the hypotensive effect of clonidine $(2\;{\mu}g/kg)$ was reduced, whereas the bradycardic effect was increased in mild hypothermic rats as compared with normothermic rats. Both hypotensive and bradycardic effects of clondine $(2\;{\mu}g/kg)$ were blocked by pretreatment with an ${\alpha}_2-adrenoceptor$ antagonist, yohimbine (0.5 mg/kg), in both thermal conditions. Yohimbine (0.5 mg/kg, i.v.) alone produced signifcantly an increase in heart rate in the mild hypothermic group than in the normothermic group. Pretreatment with a muscarinic receptor antagonist, atropine methylnitrate (1 mg/kg, i.v.), attenuated the bradycardic effect of clonidine in the mild hypothermic group but not in the normothermic group. These results suggest that clonidine- induced bradycardia is amplified by mild hypothermia probably through an increased parasympathetic activity.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.1
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• pp.91-97
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• 2017

Hyperglycemia is associated with an increased risk of cardiovascular diseases. It has been demonstrated that chronic exposure to high glucose impaired endothelial functions. However, specific effects of short-term exposure to high glucose on vascular reactivity are controversial. Moreover, the combined effects of other metabolic substrates such as free fatty acids (FFA) on vascular reactivity remain poorly understood. Here we investigate the effects of short-term exposure to high glucose with or without other metabolic substrates including FFAs termed "nutrition full" (NF) solution, on mesenteric (MA) and deep femoral arteries (DFA) of rats. Arterial ring segments were mounted in a double-wire myograph. Contraction in response to phenylephrine (PhE) was determined in control (5 mM) and high glucose (23 mM, HG) environments over a 30 min period. In both arteries, PhE-inducedvasocontraction was enhanced by pre-incubation of HG solution. A combined incubation with HG and palmitic acid ($100{\mu}M$) induced similar sensitization of PhE-contractions in both arteries. In contrast, high $K^+$-induced contractions were not affected by HG. Interestingly, pre-incubation with NF solution decreased PhE-induced contraction in MA but increased the contraction in DFA. In NF solution, the HG-induced facilitation of PhE-contraction was not observed in MA. Furthermore, the PhE-induced contraction of DFA was attenuated by HG in NF solution. Our results demonstrate that the sensitization of PhE-induced arterial contraction by HG is differentially affected by other metabolic substrates. The conversation of skeletal arterial contractility by HG in NF solution requires careful interpretation of the previous in vitro studies where only glucose is included in physiological salt solutions. Further studies are required to elucidate the mechanism underlying the inconsistent effect of NF solution on MA and DFA.

• Nutrition Research and Practice
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• v.5 no.5
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• pp.404-411
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• 2011

This study investigated the effects of freeze-dried cranberry powder on anti-inflammation and lipid profiles of lipopolysaccharide (LPS)-treated rats fed an atherogenic diet for 6 weeks. Forty Sprague-Dawley male rats (6-weeks-old) were equally divided into the following five groups: 1) normal diet group+saline (NC); 2) atherogenic diet+saline (HFC); 3) atherogenic diet+LPS (HL); 4) atherogenic diet with 5% cranberry power+LPS (C5); 5) atherogenic diet with 10% cranberry power+LPS (C10). LPS (0.5 mg/kg) was injected into the abdominal cavities of rats 18 hours prior to sacrifice. At the end of the experimental period, we measured serum lipid profiles as well as levels of serum C-reactive protein (CRP), nitric oxide (NO), and pro-inflammatory cytokines such as tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin (IL)-1${\beta}$, IL-6, and IL-10 as an anti-inflammatory cytokine. The mean serum high density lipoprotein (HDL)-cholesterol level in C5 rats was significantly higher than that in NC and HL rats (P<0.05). The mean serum levels of CRP and IL-1${\beta}$ were significantly lower (P<0.05) in the cranberry powder groups compared to those in HL rats. Additionally, mean serum IL-6 levels tended to be lower in the cranberry groups than that in the HL group, whereas serum IL-10 and NO showed 29% and 88% higher mean values in the C5 group and 49% and 24% higher in the C10 group than those in the HL group, respectively. These results suggest that freeze-dried cranberry powder may have beneficial effects on cardiovascular diseases by modifying serum lipids and the early inflammatory response.

• Nutrition Research and Practice
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• v.5 no.1
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• pp.28-33
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• 2011

Limited information from human studies indicates that dietary quercetin supplementation influences blood lipid profiles, glycemic response, and inflammatory status, collectively termed cardiometabolic risks. We tested the hypothesis that quercetin-rich supplementation, derived from onion peel extract, improves cardiometabolic risk components in healthy male smokers in a randomized, double blinded, placebo-controlled parallel design. Randomly assigned subjects were instructed to take either the placebo (n=43) or 100 mg quercetin capsules each day (n=49) for 10 weeks. Anthropometric parameters and blood pressure were measured, and blood lipids, glucose, interleukin-6, and soluble vascular cell adhesion molecule-1 (sVCAM-1) were determined at baseline and after 10 weeks of quercetin supplementation. Quercetin-rich supplementation significantly reduced serum concentrations of total cholesterol (P<0.05) and LDL-cholesterol (P<0.01), whereas these effects were not shown in the placebo group. Furthermore, significant increases were observed in serum concentrations of HDL-cholesterol both in the placebo (P<0.005) and quercetin-rich supplementation group (P<0.001); however, changes in HDL-cholesterol were significantly greater in subjects receiving quercetin-rich supplementation than the placebo. Both systolic (P<0.05) and diastolic blood pressure (P<0.01) decreased significantly in the quercetin-rich supplementation group. Glucose concentrations decreased significantly after 10 weeks of quercetin-rich supplementation (P<0.05). In contrast, no effects of quercetin-rich supplementation were observed for the inflammatory markers-IL-6 and sVCAM-1. Daily quercetin-rich supplementation from onion peel extract improved blood lipid profiles, glucose, and blood pressure, suggesting a beneficial role for quercetin as a preventive measure against cardiovascular risk.

• The Korean Journal of Physiology
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• v.23 no.1
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• pp.67-78
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• 1989

Since the atrial receptor was suggested to be involved in the control of extracellular fluid volume, it has been shown that the granularity of atrial cardiocytes can be changed by water and salt depletion, and that an extract of atrial tissue, when injected intravenously into anesthetized rats, causes a large and rapid increase in renal excretions of sodium and water. The immunoreactive atrial natriuretic peptide (ANP) has been found in the plasma of patients suffering from various cardiovascular diseases. A high level of ANP in the plasma has been reported in essential hypertension. Several studies on the effects of ANP on renal function and arterial blood pressure have presented contradictory results showing attenuated or accentuated responses. Thus, involvement of the ANP in the development of hypertension remains unresolved. Present study was undertaken to investigate whether the ANP is involved in the development of hypertension in two-kidney one-clip Goldblatt hypertensive rats. The plasma concentration of immunoreactive ANP appeared to be significantly elevated in hypertensive rats as compared with normotensive Goldblatt operated and sham-operated rats. Plasma renin concentration was higher in hypertensive rats than in normotensive rats, as observed in earlier experiments. Intravenous infusions of ANP resulted in increases of urine flow and urinary excretions of sodium and potassium in both hypertensive and normotensive rats. The renal response to ANP was markedly accentuated in Goldblatt hypertensive rats. The plasma concentration of ANP showed a linear relationship with the arterial blood pressure. Infusions of ANP reduced blood pressure both in hypertensive and normotensive rats. These results suggest that in Goldblatt hypertensive rats an elevation of ANP level in the plasma may not be a cause, but instead a consequence of hypertension, and that the renal responsiveness to the ANP is accentuated by some unknown mechanisms.

• Journal of Ginseng Research
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• v.42 no.2
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• pp.123-132
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• 2018

Ginseng has gained its popularity as an adaptogen since ancient days because of its triterpenoid saponins, known as ginsenosides. These triterpenoid saponins are unique and classified as protopanaxatriol and protopanaxadiol saponins based on their glycosylation patterns. They play many protective roles in humans and are under intense research as various groups continue to study their efficacy at the molecular level in various disorders. Ginsenosides Rb1 and Rg1 are the most abundant ginsenosides present in ginseng roots, and they confer the pharmacological properties of the plant, whereas ginsenoside Rg3 is abundantly present in Korean Red Ginseng preparation, which is highly known for its anticancer effects. These ginsenosides have a unique mode of action in modulating various signaling cascades and networks in different tissues. Their effect depends on the bioavailability and the physiological status of the cell. Mostly they amplify the response by stimulating phosphotidylinositol-4,5-bisphosphate 3-kinase/protein kinase B pathway, caspase-3/caspase-9-mediated apoptotic pathway, adenosine monophosphate-activated protein kinase, and nuclear factor kappa-light-chain-enhancer of activated B cells signaling. Furthermore, they trigger receptors such as estrogen receptor, glucocorticoid receptor, and N-methyl-$\text\tiny{D}$-aspartate receptor. This review critically evaluates the signaling pathways attenuated by ginsenosides Rb1, Rg1, and Rg3 in various tissues with emphasis on cancer, diabetes, cardiovascular diseases, and neurodegenerative disorders.

• Journal of Chest Surgery
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• v.24 no.3
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• pp.229-244
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• 1991

A bioassay technique and organ bath study were performed to analyze the effects of extracellular $Ca^{2+}$ and $Ca^{2+}$-antagonists on endothelium-derived relaxing factor[s][EDRF] released from the endothelial cells of rabbit aorta. Transverse strips with intact endothelium or damaged endothelium were used for the mechanical contraction experiment using organ bath. Long segment including thoracic and abdominal aorta with endothelium [EDRF donor aorta] was perfused with Tyrode solution which was aerated with 95% $O_2-5%$ $CO_2$ mixed gas and kept at 35oC. The perfusate was bioassayed with a transverse strip of thoracic aorta with damaged endothelium. The test strip was contracted with nor-epinephrine and acetylcholine was used to stimulate the release of EDRF from endothelial cells. The results obtained were as follows; 1] The endothelium-dependent relaxation[EDR] induced by acetylcholine was biphasic; an initial rapid relaxation followed by a slow relaxation. 2] EDR induced by acetylcholine was reduced gradually with the decrease in the concentration of extracellular $Ca^{2+}$. The effect of extracellular $Ca^{2+}$ on EDR was more prominent in the late slow relaxation phase. 3] EDR to acetylcholine was not altered by acute exposure to organic $Ca^{2+}$-antagonists. Pretreatment with verapamil to the EDRF donor aortic segment did not alter the magnitude of EDR. 4] Among the inorganic $Ca^{2+}$-antagonists $Mn^{2+}$ and $Cd^{2+}$ did not inhibit EDR, whereas $Co^{2+}$ and $La^{3+}$ inhibited EDR. 5] The inhibitory response of $Co^{2+}$ to EDR developed when infused directly on the test strip. That of $La^{3+}$, however, was evoked when added to solution perfusing the donor aortic segment. The above results suggest that $Ca^{2+}$-antagonists do not affect EDR and the inhibitory effect of $Ca^{2+}$ results from influencing the action of EDRF on vascular smooth muscle, whereas that of $La^{3+}$ results from its action on the release of EDRF from endothelial cells.

• Journal of Chest Surgery
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• v.28 no.6
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• pp.542-548
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• 1995

The goal of this study is to develop an effective control system for cardiac output regulation based upon the preload and afterload conditions without any transducers and compliance chambers in the moving actuator type total artificial heart. Motor current waveforms during the actuator movement are used as an input to the automatic control algorithm. While the current waveform analysis is performed, the stroke length and velocity of the actuator are gradually increased up to the maximum pump output level. If the diastolic filling rate of either right or left pump begins to exceed the venous return, atrial collapse will occur. Since the diastolic suction acts as a load to the motor, this critical condition can be detected by analyzing the motor current waveforms. Every time this detection criterion is met, the control algorithm decreases the stroke velocity and length of the actuator step by step just below the critical detection level. Then, they start to increase. In this way the maximum pump output under given venous return can be achieved. Additionally the control algorithm provides some degree of afterload sensitivity. If the aortic pressure is detected to exceed 120 mmHg, the stroke length and velocity decrease in the same way as the response to the preload. Left-right pump output balance is maintained by proper adjustment of the asymmetry of the stroke angle. In the mock circulatory test, this control system worked well and there was a considerable range of stroke volume difference with adjustment of the asymmetry value. Two ovine experiments were performed. It was confirmed that the required cardiac output regulation according to the venous return could be achieved with adequate detection of diastolic function, at least in the in vivo short-term survival cases[2-3 days . We conclude that this control algorithm is a promising method to regulate cardiac output in the moving actuator type total artificial heart.