• Science of Emotion and Sensibility
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• v.8 no.2
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• pp.95-101
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• 2005

This study is based on previous information regarding reduced cardiac vagal activity in patients with coronary artery disease(CAD), on reduced variance(SDNN : standard deviation of all normal RR intervals), low-frequency power(LF), and the complexity of heart rate variability(HRV) in patients with chronic heart failure(CHF), and on the normalized high-frequency power of HRV is the highest in the right lateral decubitus position among 3 recumbent postures in patients with CAD, However, nothing is known about the nonlinear dynamics of HRV for the 3 recumbent postures in patients with CAD. To investigate the linear and non-linear characteristics of HRV in patients with CAD, 29 patients as CAD group and 23 patients as control group were studied. Electrocardiogram(ECG) with lead II channel was measured on these patients for 3 recumbent postures in random order. The HRV from ECG was analyzed with linear method(for time and frequency domains) and nonlinear method. The lower the high-frequency power in normalized unit(nHF) in the supine or left lateral decubitous position, the higher the increase in nHF when the position was changed from supine or left lateral decubitous to right lateral decubitous. Among the 3 recumbent postures in patients with severe CAD, the right lateral decubitus position was observed to induce the highest vagal modulation, the lowest sympathetic modulation, and the highest complexity of human physiology system.

• Journal of Preventive Medicine and Public Health
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• v.38 no.3
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• pp.276-282
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• 2005

Objectives : To evaluate the predictive validity of three scoring systems; the acute physiology and chronic health evaluation(APACHE) III, simplified acute physiology score(SAPS) II, and mortality probability model(MPM) II systems in critically ill patients. Methods : A concurrent and retrospective study conducted by collecting data on consecutive patients admitted to the intensive care unit(ICU) including surgical, medical and coronary care unit between January 1, 2004, and March 31, 2004. Data were collected on 348 patients consecutively admitted to the ICU(aged 16 years or older, no transfer, ICU stay at least 8 hours). Three models were analyzed using logistic regression. Discrimination was assessed using receiver operating characteristic(ROC) curves, sensitivity, specificity, and correct classification rate. Calibration was assessed using the Lemeshow-Hosmer goodness of fit H-statistic. Results : For the APACHE III, SAPS II and MPM II systems, the area under the receiver operating characterist ic(ROC) curves were 0.981, 0.978, and 0.941 respectively. With a predicted risk of 0.5, the sensitivities for the APACHE III, SAPS II, and MPM II systems were 81.1, 79.2 and 71.7%, the specificities 98.3, 98.6, and 98.3%, and the correct classification rates 95.7, 95.7, and 94.3%, respectively. The SAPS II and APACHE III systems showed good calibrations(chi-squared H=2.5838 p=0.9577 for SAPS II, and chi-squared H=4.3761 p=0.8217 for APACHE III). Conclusions : The APACHE III and SAPS II systems have excellent powers of mortality prediction, and calibration, and can be useful tools for the quality assessment of intensive care units(ICUs).

• The Korean Journal of Nuclear Medicine
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• v.32 no.1
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• pp.1-9
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• 1998

Gated myocardial SPECT and attenuation correction gave birth to new insights into the pathophysiology of ischemic myocardial perfusion and function in clinical routine practice. Gated myocardial Tc-99m-compound SPECT improved diagnostic accuracy of coronary artery disease and enabled us to observe motion and thickening of myocardial walls as well as myocardial perfusion at the same time. Quantitative and qualitative assessment of myocardial performance and perfusion let us to understand the myocardial physiology in ischemia and infarction. In every patient who underwent gated perfusion SPECT, we will find ejection fraction, left ventricular volumes and regional wall motion. There are hopes to use gated TI-201 SPECT for the same purpose and to use gated SPECT for evaluation of wall motion and thickening at stress or immediate post-stress. Attenuation correction could improve diagnostic accuracy mainly by increasing normalcy ratio or performance of non-expert physicians. Both gated methods and attenuation correction improved specificity of non-expert physicians in diagnosing patients with moderate pretest likelihood. New imaging techniques will fill the desire of cardiologists to examine function and perfusion, and possibly metabolism in their clinical routine practice.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.4
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• pp.407-413
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• 2017

Vascular reactivity can be influenced by the vascular region, animal age, and pathologies present. Prostaglandins (produced by COX-1 and COX-2) play an important role in the contractile response to phenylephrine in the abdominal aorta of young rats. Although these COXs are found in many tissues, their distribution and role in vascular reactivity are not clear. At a vascular level, they take part in the homeostasis functions involved in many physiological and pathologic processes (e.g., arterial pressure and inflammatory processes). The aim of this study was to analyze changes in the contractile response to phenylephrine of thoracic/abdominal aorta and the coronary artery during aging in rats. Three groups of rats were formed and sacrificed at three distinct ages: prepubescent, young and old adult. The results suggest that there is a higher participation of prostanoids in the contractile effect of phenylephrine in pre-pubescent rats, and a lower participation of the same in old rats. Contrarily, there seems to be a higher participation of prostanoids in the contractile response of the coronary artery of older than pre-pubescent rats. Considering that the changes in the expression of COX-2 were similar for the three age groups and the two tissues tested, and that expression of COX-1 is apparently greater in older rats, COX-1 and COX-2 may lose functionality in relation to their corresponding receptors during aging in rats.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.4
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• pp.165-170
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• 2008

In the present study, we aimed to identify the synergistic effects of concurrent treatment of low concentrations of cilostazol and probucol to inhibit the oxidative stress with suppression of inflammatory markers in the cultured human coronary artery endothelial cells (HCAECs). Combination of cilostazol (0.3${\sim}3{\mu}$M) with probucol (0.03${\sim}0.3{\mu}$M) significantly suppressed TNF-${\alpha}$-stimulated NAD(P)H-dependent superoxide, lipopolysaccharide (LPS)-induced intracellular reactive oxygen species (ROS) production and TNF-${\alpha}$ release in comparison with probucol or cilostazol alone. The combination of cilostazol (0.3${\sim}3{\mu}$M) with probucol (0.1${\sim}0.3{\mu}$M) inhibited the expression of vascular cell adhesion molecule-1 (VCAM-1) and monocyte chemoattractant protein-1 (MCP-1) more significantly than did the monotherapy with either probucol or cilostazol. In line with these results, combination therapy significantly suppressed monocyte adhesion to endothelial cells. Taken together, it is suggested that the synergistic effectiveness of the combination therapy with cilostazol and probucol may provide a beneficial therapeutic window in preventing atherosclerosis and protecting from cerebral ischemic injury.

• Journal of Ginseng Research
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• v.23 no.4
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• pp.235-238
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• 1999

ATP-sensitive $K^+$ channels $(K_{ATP})$ are expressed in vascular smooth muscle cells, skeletal muscle cells, pancreatic ${\beta}$ cells, neurons and epithelial cells. $K_{ATP}$ contributes to regulate membrane potential to control vascular tone, to protect myocardial ischemia, and to regulate insulin secretion in pancreatic ${\beta}$ cells. We previously demonstrated that ginseng saponins and ginsenoside $Rg_3$ activated maxi $Ca^{2+}-activated\;K^+$ channel, and this might cause vasodilation. Because $K_{ATP}$ plays an important roles to regulate the resting membrane potential in vascular smooth muscle cells, we investigated whether ginsenoside $Rg_3$ produces vasodilation by activating $K_{ATP}$ We showed in this study that $K_{ATP}$ is expressed in rabbit coronary artery smooth muscle cells. $K_{ATP}$ was inwardly rectifying and was inhibited by intemal application of ATP. Micromolar minoxidil activated, but glyburide inhibited the activity of $K_{ATP}$ Ginsenoside $Rg_3$ relieved inactivaiton of whole-cell $K_{ATP}$ current without affecting the peak amplitude of $K_{ATP}$ currents presumably due to more opening of the channels.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.2
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• pp.147-157
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• 2021

Coronary microembolization (CME) is associated with cardiomyocyte apoptosis and cardiac dysfunction. Puerarin confers protection against multiple cardiovascular diseases, but its effects and specific mechanisms on CME are not fully known. Hence, our study investigated whether puerarin pretreatment could alleviate cardiomyocyte apoptosis and improve cardiac function following CME. The molecular mechanism associated was also explored. A total of 48 Sprague-Dawley rats were randomly divided into CME, CME + Puerarin (CME + Pue), sham, and sham + Puerarin (sham + Pue) groups (with 12 rats per group). A CME model was established in CME and CME + Pue groups by injecting 42 ㎛ microspheres into the left ventricle of rats. Rats in the CME + Pue and sham + Pue groups were intraperitoneally injected with puerarin at 120 mg/kg daily for 7 days before operation. Cardiac function, myocardial histopathology, and cardiomyocyte apoptosis index were determined via cardiac ultrasound, hematoxylin-eosin (H&E) and hematoxylin-basic fuchsin-picric acid (HBFP) stainings, and TdT-mediated dUTP nick-end labeling (TUNEL) staining, respectively. Western blotting was used to measure protein expression related to the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/glycogen synthase kinase-3β (GSK-3β) pathway. We found that, puerarin significantly ameliorated cardiac dysfunction after CME, attenuated myocardial infarct size, and reduced myocardial apoptotic index. Besides, puerarin inhibited cardiomyocyte apoptosis, as revealed by decreased Bax and cleaved caspase-3, and up-regulated Bcl-2 and PI3K/Akt/GSK-3β pathway related proteins. Collectively, puerarin can inhibit cardiomyocyte apoptosis and thus attenuate myocardial injury caused by CME. Mechanistically, these effects may be achieved through activation of the PI3K/Akt/GSK-3β pathway.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.5
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• pp.335-345
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• 2022

Pyroptosis is an inflammatory form of programmed cell death that is linked with invading intracellular pathogens. Cardiac pyroptosis has a significant role in coronary microembolization (CME), thus causing myocardial injury. Tanshinone IIA (Tan IIA) has powerful cardioprotective effects. Hence, this study aimed to identify the effect of Tan IIA on CME and its underlying mechanism. Forty Sprague-Dawley (SD) rats were randomly grouped into sham, CME, CME + low-dose Tan IIA, and CME + high-dose Tan IIA groups. Except for the sham group, polyethylene microspheres (42 ㎛) were injected to establish the CME model. The Tan-L and Tan-H groups received intraperitoneal Tan IIA for 7 days before CME. After CME, cardiac function, myocardial histopathology, and serum myocardial injury markers were assessed. The expression of pyroptosis-associated molecules and TLR4/MyD88/NF-κB/NLRP3 cascade was evaluated by qRT-PCR, Western blotting, ELISA, and IHC. Relative to the sham group, CME group's cardiac functions were significantly reduced, with a high level of serum myocardial injury markers, and microinfarct area. Also, the levels of caspase-1 p20, GSDMD-N, IL-18, IL-1β, TLR4, MyD88, p-NF-κB p65, NLRP3, and ASC expression were increased. Relative to the CME group, the Tan-H and Tan-L groups had considerably improved cardiac functions, with a considerably low level of serum myocardial injury markers and microinfarct area. Tan IIA can reduce the levels of pyroptosis-associated mRNA and protein, which may be caused by inhibiting TLR4/MyD88/NF-κB/NLRP3 cascade. In conclusion, Tanshinone IIA can suppress cardiomyocyte pyroptosis probably through modulating the TLR4/MyD88/NF-κB/NLRP3 cascade, lowering cardiac dysfunction, and myocardial damage.

• Journal of Ginseng Research
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• v.37 no.3
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• pp.283-292
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• 2013

Ginsenosides are divided into two groups based on the types of the panaxadiol group (e.g., ginsenoside-Rb1 and -Rc) and the panaxatriol group (e.g., ginsenoside-Rg1 and -Re). Among them, ginsenoside-Re (G-Re) is one of the compounds with the highest content in Panax ginseng and is responsible for pharmacological effects. However, it is not yet well reported if G-Re increases the hemodynamics functions on ischemia (30 min)/reperfusion (120 min) (I/R) induction. Therefore, in the present study, we investigated whether treatment of G-Re facilitated the recovery of hemodynamic parameters (heart rate, perfusion pressure, aortic flow, coronary flow, and cardiac output) and left ventricular developed pressure (${\pm}dp/dt_{max}$). This research is designed to study the effects of G-Re by studying electrocardiographic changes such as QRS interval, QT interval and R-R interval, and inflammatory marker such as tissue necrosis factor-${\alpha}$ (TNF-${\alpha}$) in heart tissue in I/R-induced heart. From the results, I/R induction gave a significant increase in QRS interval, QT interval and R-R interval, but showed decrease in all hemodynamic parameters. I/R induction resulted in increased TNF-${\alpha}$ level. Treatment of G-Re at 30 and $100{\mu}M$ doses before I/R induction significantly prevented the decrease in hemodynamic parameters, ameliorated the electrocardiographic abnormality, and inhibited TNF-${\alpha}$ level. In this study, G-Re at $100{\mu}M$ dose exerted more beneficial effects on cardiac function and preservation of myocardium in I/R injury than $30{\mu}M$. Collectively, these results indicate that G-Re has distinct cardioprotectective effects in I/R induced rat heart.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.1
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• pp.17-21
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• 2018

Our previous studies have confirmed that morroniside has neuroprotective effects. However, the effects of morroniside on cardiac myocardium remain unknown. Rats were anaesthetized with 10% chloral hydrate (0.35~0.4 mL/kg) and an acute myocardial infarction (AMI) was induced by ligating the anterior descending coronary artery (LAD). Following AMI, morroniside was administered intragastrically for 3 consecutive days at doses of 45, 90 and 180 mg/kg, respectively. Lactate dehydrogenase (LDH) and cardiac troponin T (cTnT) activities in AMI rats in the serum were detected with commercial kits. The expression of IL-6, $IL-1{\beta}$ and $TNF-{\alpha}$ in myocardium was detected by Western blotting analysis. We observed a significant decline in the Q(q) wave amplitude in morroniside-treated rats after 72 h. Additionally, treatment of morroniside decreased the levels of LDH and cTnT in AMI rats. We also observed that morroniside reduced the expression of IL-6, $IL-1{\beta}$ and $TNF-{\alpha}$ in myocardium. Taken together, our findings demonstrate that morroniside had effective anti-inflammatory properties in AMI rats.