• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2001.11a
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• pp.91-95
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• 2001

In this study, we estimated the behavior of the diversity of physiological responses under varied physical environmental factors by measuring variations of heart rate variability (HRV), an index of activity of cardiac autonomic control. Seven healthy young male adults consented and participated in the study. The environmental conditions consisted of thermal, lighting, and acoustic conditions. Two components of HRV were measured. one was the low frequency (LF) component of HRV, which provided a quantitative index of the sympathetic and parasympathetic (vagal) activities controlling the heart rate (HR). The other component measured was the high frequency (HF) component, which provided an index of the vagal tone. The percent contribution of physical environmental factors to the variations in HRV indices were calculated by ANOVA. The contribution of physical environmental factors to the variations in HR was higher than the contribution of HF and LF. However, the contribution of these factors was lower than the contribution related with individual difference in all indices. This result showed that the individual diversity of physiological responses is not a negligible quantity.

• Proceedings of the Korean Biophysical Society Conference
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• 2001.06a
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• pp.67-67
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• 2001

Our previous studies showed that the relaxation defect of diabetic heart was due to the changes in the expressional levels of SR $Ca^{2＋}$-ATPase and PLB. In the diabetic heart contractile abnormalities were also observed, and one of the mechanisms for these changes could include alterations in the expression and/or activity levels of various $Ca^{2＋}$ regulatory proteins involving cardiac contraction.(omitted)

• Archives of Pharmacal Research
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• v.8 no.4
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• pp.267-272
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• 1985

Pyrantal pamoate's anthelmintic activity is due to its action as a neuromuscular blocking agent. It is generally well tolerated. Transient rises in SGOT levels have been reported in the drug-treated patients. Decreased levels of serum alkaline phosphatase post treatment were found in yound dogs. The present study was performed to investigate the possible toxic effects of pyrantal pamoate in pregnant mice progenies. The drug was given in different doses to these mothers in the first, second and third trimester. Serum alkaline phosphatase, SGOT and SGPT of one or two month old offspring were monitored. SGOT levels showed an increase in some doses in one and two month old offspring where alkaline phosphatase showed a decrease in some doses in one and two month old offspring. The latter effect may be due to osteoblastic alkaline phosphatase inhibition. The effect on SGOT levels, however, was difficult to explain, but may be due to a toxic effect on liver cells or cardiac muscles.

• Journal of Pharmacopuncture
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• v.20 no.4
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• pp.243-256
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• 2017

Doxorubicin as a chemotherapeutic drug is widely used for the treatment of patients with cancer. However, clinical use of this drug is hampered by its cardiotoxicity, which is manifested as electrocardiographic abnormalities, arrhythmias, irreversible degenerative cardiomyopathy and congestive heart failure. The precise mechanisms underlying the cardiotoxicity of doxorubicin are not clear, but impairment of calcium homeostasis, generation of iron complexes, production of oxygen radicals, mitochondrial dysfunction and cell membrane damage have been suggested as potential etiologic factors. Compounds that can neutralize the toxic effect of doxorubicin on cardiac cells without reducing the drug's antitumor activity are needed. In recent years, numerous studies have shown that herbal medicines and bioactive phytochemicals can serve as effective add-on therapies to reduce the cardiotoxic effects of doxorubicin. This review describes different phytochemicals and herbal products that have been shown to counterbalance doxorubicin-induced cardiotoxicity.

• Proceedings of the Korean Biophysical Society Conference
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• 1997.07a
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• pp.28-28
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• 1997

Stimulation of $\alpha$$_1$-adrenergic receptor ($\alpha$$_1$-AR) by phenylephrine produced a decrease in intracellular N $a^{＋}$ activity ( $a_{Na}$ $^{i}$ ) in multicellular preparations of cardiac tissues. The role of protein kinase C (PKC) in $\alpha$$_1$-adrenergic regulation of $a_{Na}$ $^{i}$ was studied in single ventricular myocyte isolated from guinea pig hearts. $a_{Na}$ $^{i}$ and membrane potential were measured with N $a^{+}$ indicator, sodium-binding benzofuran isophthalate tetraacetoxy methyl ester (SBFI/AM) and microelectrodes respectively when ventricular myocyte was stimulated at 0.3 Hz.(omitted)d)

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.143.1-143.1
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• 2003

In this study. we investigated whether the cardioprotective effect shown by quercetin 3-O-$\alpha$-arabinofuranoside extracted from Lindera erythrocarpa against ROS-induced cell death in H9c2 cardiac myocytes. Cell death was induced by BSO, buthionine sulfoximine, which inhibits GSH level and subsequntly increase ROS level. Cell death was quntitatively determined by measuring lactate dehydrogenase (LDH) activity. (omitted)

• Journal of Chest Surgery
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• v.37 no.10
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• pp.817-826
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• 2004

Background: Several studies have demonstrated that conventional hypothermic cardiopulmonary bypass (CPB) causes cellular injury, abnormal responses in peripheral vascular beds and increased postoperative bleeding, whereas normothermic CPB provides protection of the hypothermic-induced effects and better cardiac recovery. The present study was prospectively performed to compare the effects of normothermic CPB to those of hypothermic CPB on the inflammatory and hematologic responses during cardiac surgery. Material and Method: Thirty-four adult patients scheduled for elective cardiac surgery were randomly assigned to hypothermic CPB (nasopharyngeal temperature $26～28^{\circ}C,$ n=17) or normothermic CPB (nasopharyngeal $temperature>35.5^{\circ}C,$ n=17) group. In both groups, cold $(4^{\circ}C)$ crystalloid cardioplegia was applied for myocardial protection. Blood samples were drawn from radial artery before (Pre-CPB), 10 minutes after starting (CPB-10) and immediately after ending (CPB-OFF) CPB. Total leukocyte and platelet counts, interleukin-6 (IL-6) level(expressed as percent to the baseline of Pre-CPB), D-dimer level, protein C and protein S activity were measured with the blood samples. The amount of bleeding for postoperative 24 hours and blood transfusion after operation were also assessed. All parameters were compared between the two groups. Result: The total leukocyte counts $(10,032\pm65/mm^3)$ and the increased ratio of IL-6 $(353\pm7.0%)$ at CPB-OFF in the normothermic group were higher than that $(7,254\pm48/mm^3$ and $298\pm7.3%)$ of the hypothermic group(p=0.02 and p=0.03). In the normothermic group, protein C activity $(32\pm3.8%)$ and protein S activity $(35\pm4.1%)$ at CPB-OFF were significantly lower than that $(45\pm4.3%$ and $51\pm3.8%)$ of the hypothermic group (p=0.04 and p=0.009). However, there were no differences in platelet counts and D-dimer concentration. In the normothermic group, the amount of bleeding for postoperative 24 hours $(850\pm23.2$ mL) and requirements for blood transfusion after operation such as packed cell $(1,402\pm20.5$ mL), fresh frozen plasma $(970\pm20.8$ mL) and platelet $(252\pm6.4$ mL) were higher than that $(530\pm21.5$ mL, $696\pm15.7$ mL, $603\pm18.2$ mL and $50\pm0.0$ mL) of the hypothermic group. Conclusion: These results indicate that normothermic CPB with cold crystalloid cardioplegia was associated with higher increase in inflammatory response, hemostatic abnormalities and postoperative bleeding problem than moderate hypothermic CPB.

• Journal of Chest Surgery
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• v.33 no.5
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• pp.398-406
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• 2000

Background: Cardiac atrium is an endocrine gland secreting a family of natriuretic peptides. The secretion of atrial natriuretic peptide(ANP) had been shown to be controlled by variable factors. The change in atrial dynamics have been considered as one of the most prominent stimuli for the stimulation of ANP secretion. Hypoxic stress has been shown to increase cardiac ANP secretion. However, the mechanism by which hypoxia increases ANP secretion cardiac ANP secretions. However, the mechanism by which hypoxia increases ANP secretion has not to be defined. Therefore, the purpose of the present study was tow-fold: to develop a protocol to defined the effect of hypoxia on ANP secretion in perfused beating rabbit atria and to clarify the mechanism responsible for the accentuation by hypoxia of ANP secretion. Material and Method: Experiments have been done in perfused beating rabbit atria. ANP was measured by radioimmunoassay. Result: Hypoxic stimulus with nitrogen decreased atrial stroke volume. The decrease in atrial stroke volume recovered basal level during the period of recovery with oxygen. ANP secretion and the concentration of perfusate ANP in terms of extracellular fluid(ECF) translocation which reflects the rate of myocytic release of ANP were increased by hypoxia and returned to basal levels during the recovery. Changes in ECF translocation paralleled by hypoxia and returned to basal levels during the recovery. Changes in ECF translocation paralleled to that of atrial stroke volume. At the start of recovery in atrial storke volume, ECF tranalocation incrased for several minutes. The above responses were stable and reproducible. Glibenclamide treatment prevented the recovery in atrial stroke volume. Increments by hypoxia of ANP secretion and ANP concentration were suppressed by glibenclamide. Conclusion: These results indicate that hypoxia incrased atrial myocytic ANP release and that the mechanism responsible for the accentuation is partially related to the change in K+ATP channel activity.

• The Korean Journal of Physiology and Pharmacology
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• v.11 no.2
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• pp.57-64
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• 2007

Ischemic preconditioning (IPC) is known to protect the heart against ischemia/reperfusion (IR)-induced injuries, and regional differences in the mitochondrial antioxidant state during IR or IPC may promote the death or survival of viable and infarcted cardiac tissues under oxidative stress. To date, however, the interplay between the mitochondrial antioxidant enzyme system and the level of reactive oxygen species (ROS) in the body has not yet been resolved. In the present study, we examined the effects of IR- and IPC-induced oxidative stresses on mitochondrial function in viable and infarcted cardiac tissues. Our results showed that the mitochondria from viable areas in the IR-induced group were swollen and fused, whereas those in the infarcted area were heavily damaged. IPC protected the mitochondria, thus reducing cardiac injury. We also found that the activity of the mitochondrial antioxidant enzyme system, which includes manganese superoxide dismutase (Mn-SOD), was enhanced in the viable areas compared to the infarcted areas in proportion with decreasing levels of ROS and mitochondrial DNA (mtDNA) damage. These changes were also present between the IPC and IR groups. Regional differences in Mn-SOD expression were shown to be related to a reduction in mtDNA damage as well as to the release of mitochondrial cytochrome c (Cyt c). To the best of our knowledge, this might be the first study to explore the regional mitochondrial changes during IPC. The present findings are expected to help elucidate the molecular mechanism involved in IPC and helpful in the development of new clinical strategies against ischemic heart disease.

• Clinical and Experimental Reproductive Medicine
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• v.29 no.2
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• pp.139-147
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• 2002

Objective : This study was to establish a reproducible differentiation system from the parthenogenetic mouse embryonic stem (P-mES02) cells into functional cardiomyocytes like as in vitro fertilization mouse embryonic stem (mES01) cells. Materials and Methods: To induce differentiation, P-mES02 cells were dissociated and aggregated in suspension culture environment for embryoid body (EB) formation. For differentiation into cardiomyocytes, day 4 EBs were treated with 0.75% dimethyl sulfoxide (DMSO) for another 4 days (4-/4+) and then were plated onto gelatin-coated dish. Cultured cells were observed daily using an inverted light microscope to determine the day of contraction onset and total duration of continuous contractile activity for each contracting focus. This frequency was compared with the results of DMSO not treated P-mES02 group (4-/4-) and mES01 groups (4-/4+ or 4-/4-). For confirm the generation of cardiomyocytes, beating cell masses were treated with trypsin-EDTA, dispersed cells were plated onto glass coverslips and incubated for 48 h. Attached cells were fixed using 4% paraformaldehyde and incubated with specific antibodies (Abs) to detect cardiomyocytes (anti-sarcomeric ? -actinin Ab, 1 : 100; anti-cardiac troponin I Ab, 1 : 2000) for 1 h. And the cells were finally treated with FITC or TRITC labelled 2nd Abs, respectively, then they were examined under fluorescence microscopy. Results: Rhythmically contracting areas in mES01 or P-mES02 cells were firstly appeared at 9 or 10 days after EBs plating, respectively. The highest cumulative frequency of beating EBs was not different in both treatment groups (mES01 and P-mES02, 4-/4+) with the results of 61.3 % at 13 days and 69.8% at 15 days, respectively. Also, the contracting duration of individual beating EBs was different from minimal 7 days to maximal 53 days. However, DMSO not treated groups (mES01 and P-mES02, 4-/4-) also had contracting characteristics although their frequency was a few compared to those of DMSO treated groups (6.0% and 4.0%). Cells recovered from the spontaneously contracting areas within EBs in both treated groups were stained positively with muscle specific anti-sarcomeric ? -actinin Ab and cardiac specific anti-cardiac troponin I Ab. Conclusion: This study demonstrated that the P-mES02 cell-derived cardiomyocytes displayed similarly structural properties to mES01 cell-derived cardiomyocytes and that the DMSO treatment enhanced the cardiomyocytes differentiation in vitro.