• Journal of Chest Surgery
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• v.16 no.2
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• pp.199-212
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• 1983

The inhibition/influences of adenine compounds on the heart have been described repeatedly by many investigators, since the first report by Druny and Szent-Gyorgyi [1929]. These studies have shown that adenosine and adenine nucleotides have an over-all effect similar to that of acetylcholine [ACh] by slowing and weakening the heartbeat. The basic cellular and membrane events underlying the inhibitory action of adenosine on sinus rate, however, are not well understood. Furthermore, the physiological role of adenosine in regulation of the heartbeat remains still to be elucidated. Therefore, this study was undertaken in order to examine the response of rabbit SA node to adenosine and to compare the response to that of ACh. Isolated SA node preparation, whole atrial pair, or left atrlal strip was used in each experiment. Action potentials of SA node were recorded through the intracellular glass microelectrodes, which were filled with 3M KCI and had resistance of 30-50 M. All experiments were performed in a bicarbonate-buffered Tyrode solution which was aerated with 3% $CO_2-97%$ $O_2$ gas mixture and kept at $35^{\circ}C$. Spontaneous firing rate of SA node at 35C [Mean + SEM, n=16] was 154 + 3.3 beats/min. The parameters of action potentials were: maximum astolic potential [MDP], -731.7mV: overshoot [OS], 9 + 1.4mV; slope of pacemaker potential [SPP], 94 3.0mV/sec.Adenosine suppressed the firing rate of SA node in a dose dependent manner. This inhibitory effect appeared at the concentration of $10^{-6}M$ and was potentiated in parallel with the increase in adenosine concentration. Changes in action potential by adenosine were dose-dependent increase of MDP and decrease of SPP until $10^{-4}$. Above this concentration, however, the amplitude of action potential decreased markedly due to the simultaneous decrease of both MDP and OS. All these effects of adenosine were not affected by pretreatment of atropine [2mg/l] and propranolol [$5{\times}10^{-6}M$]. ACh [$10^{-6}M$] responses on action potential were similar to those of adenosine by increasing MDP and decreasing SPP. These effects of ACh disappeared by pretreatment of atropine [2mg/1]. Inhibition/effects of adenosine and ACh on sinus rate were enhanced synergistically with the simultaneous administration of adenosine and ACh. Marked decrease of overshoot potential was the most prominent feature on action potential. Dipyridamole [DPM], which is known to block the adenosine transport across cell membrane, definitely potentiated the action of adenosine . Adenosine suppressed the sinus rate and atrial contractility in the same dosage range, even in the reserpinized preparation. Above` results suggest that adenosine suppresses pacemaker activity, like ACh, by acting directly on the membrane of SA node, increasing MDP and decreasing SPP.

• The Korean Journal of Physiology
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• v.20 no.1
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• pp.17-29
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• 1986

The present study was carried out to observe the effect of triiodothyronine on heart, one of the target organ of thyroid hormone. There are many reports that tachycardia, arrythmia, and agumentation of sodium, potassium pump activity are caused in hyperthyroid animal. To examine these cardiac positive chronotropic effects on sinoatrial (SA) node and atrial muscle, hyperthyroid state was induced experimentally by the injecion of 3,3',5-1-triiodothyronine $(T_3)$ in $3{\sim}6$ month-old rabbits. Then intracellular recordings by inserting glass microelectrode into cell were obtained in SA node and atrial muscle. The results can be summarized as follows : 1) Heartbeat was increased from $169.6{\pm}28.0\;to\;264.2{\pm}18.0$ beats per minute, while body weight was decreased to 68f of the initial body weight (Day 1). 2) In experimental group, the duration of action potential at 80% repolarization was decreased from $148.0{\pm}29.1\;to\;107{\pm}13.6msec$. This suggested the increase heartbeat. 3) The firing rate in hyperthyroid group markedly reduced under the 15 mM potassium Tyrode (p<0.005). 4) In hyperthyroid group, depolarization of atrial muscle cell was lowered significantly in 15 mM (p<0.05), 20 mM (p<0.05) potassium Tyrode solution. 5) Sodium-potassium pump activities in experimental group were higher than those in control group in both SA node (p<0. 1) and atrial muscle (p<0.025). 6) In lower concentration of $MnCl_2$, the excitability of SA node in hyperthyroid group was decreased more than that in control group. Effective inhibitory dose $(ID_{50})$ as 0.6 mM in hyperthyroid statd and 1.1 mM in control group.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.5
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• pp.934-944
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• 2011

This study was designed to investigate the effects of Kyungohkgo to improve aerobic capacity and eliminate exercise-induced fatigue in high school soccer players. Twenty four subjects were participated and randomly assigned into two groups [KG, Kyungohkgo group (n=12); PG, Placebo control group (n=12)]. Two groups were completed treadmill exercise protocol using graded exercise test at before and after experimental treatment of 4 weeks. The $VO_2$max and endurance time were measured by gas analysis and heart rate (HR) was measured by polar system at pre, post 0, post 5, post 15, post 30 and post 60 minutes. Blood samples were collected to analyze blood components. 1. The $VO_2$max was significant increased in the group of after intake Kyungohkgo compared to the group of after intake placebo (p<.05). 2. The HR was significant decreased in the group of after intake Kyungohkgo compared to the group of after intake placebo during recovery time at post 5 mins(p<.05), 30 mins(p<.01), 60 mins(p<.01). 3. Weight, body mass index, percent body fat, anaerobic threshold, endurance time, blood lactate concentrate, lactate dyhydrogenase, creatine kinase, serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, other energy sources(total-cholesterol, triglyceride, high density lipoprotein-cholesterol, low density lipoprotein-cholesterol, creatinine) and electrolyte (Na, K, Cl) were shown no significant differences between groups. These results suggested that Kyungohkgo can be used as ergogenic aids to improve aerobic capacity and eliminate exercise-induced fatigue.

• Journal of the Korean Society of Physical Medicine
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• v.14 no.4
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• pp.133-142
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• 2019

PURPOSE: This study examined the effectiveness of an active lifestyle on the HRV and fitness of the older female adults. METHODS: Eighty female older adults (72.68±3.78 years) were sampled from a senior wellness institute. Accelerometers were distributed to each participant to have the device attached to them for one week, and the physical activity data (Energy expenditure in Kcal) of each participant were analyzed. Participants were divided into 3 groups (<1,000 Kcal vs 1,000 to 1,500 Kcal vs ≥1,500 Kcal) based on the amount of weekly physical activity. Before and after data analysis, the HRV was measured at resting state and the Senior Fitness Test was performed. RESULTS: One way ANOVA showed a significant difference in the HRV between the three groups. Group A (≥ 1,500 Kcal) was superior in HF and HF/HF + LF whereas Group C (<1,000 Kcal) showed high level of LF, LF/HF, and LF/HF+LF. The same statistics revealed significant differences in fitness. Most of the fitness variables were superior in Group A and B compared to Group C. Significant correlations were observed between physical activity and both HRV and in fitness. CONCLUSION: Theses results suggest that an active lifestyle may be an effective intervention for the prevention of both cardiometabolic disorder and improvement of the fitness level in older female adults.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.2
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• pp.121-125
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• 2013

The purpose of this study is to investigate the antinociceptive effects of ginsenosides on toothache. c-Fos immunoreactive (IR) neurons were examined after noxious intrapulpal stimulation (NS) by intrapulpal injection of 2 M KCl into upper and lower incisor pulps exposed by bone cutter in Sprague Dawley rats. The number of Fos-IR neurons was increased in the trigeminal subnucleus caudalis (Vc) and the transitional region between Vc and subnucleus interpolaris (Vi) by NS to tooth. The intradental NS raised arterial blood pressure (BP) and heart rate (HR). The number of Fos-IR neurons was also enhanced in thalamic ventral posteromedial nucleus (VPMN) and centrolateral nucleus (CLN) by NS to tooth. The intradental NS increased the number of Fos-IR neurons in the nucleus tractus solitarius (NTS) and rostral ventrolateral medulla (RVLM), hypothalamic supraoptic nucleus (SON) and paraventricular nucleus (PVN), central cardiovascular regulation centers. Ginsenosides reduced the number of c-Fos-IR increased by NS to tooth in the trigeminal Vc and thalamic VPMN and CLN. Naloxone, an opioid antagonist, did not block the effect of ginsenoside on the number of Fos-IR neurons enhanced by NS to tooth in the trigeminal Vc and thalamic VPMN and CLN. Ginsenosides ameliorated arterial BP and HR raised by NS to tooth and reduced the number of Fos-IR neurons increased by NS to tooth in the NTS, RVLM, hypothalamic SON, and PVN. These results suggest that ginsenosides have an antinociceptive effect on toothache through non-opioid system and attenuates BP and HR increased by NS to tooth.

• Korean Journal of Environment and Ecology
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• v.12 no.4
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• pp.398-405
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• 1999

This study was carried out to investigate exercise load of visitors and physical condition of stairway in the trail of Keumsan located in Hallyo-Haesang National Park. Total trail length of Keumsan is 2,126m, and the number of step-trail section are 15, and the total length of step-trail section is 1,000.4m. Average gradient of step-trail was 20~40%. But the gradient and length were 45.7% and 268.5m in the section 11, and 58.4% and 188.6m in the section 12. The greatest gradient was 67.8% in the section 13. During the climbing in trail, heart rate were 104~184beats/min.. And in the step-trail section 11, 12, and 13, IHR, ELI, and %HRmax were 166.5%, 89.1%, 92.9%, and 167.4%, 89.6%, 93.2%, and 157.8%, 84.5%, 89.9%, respectively.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1998.04a
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• pp.163-185
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• 1998

The purpose of this study was to analyze the physiology changes by circuit weight training(CWT). The subject of this study consists of 16 student on ship(experimental groups(SE) N=8, control group(SCa) N=8) and 16 students on land (experimental groups(LE) n=8, control groups(LCb) N=8). The items of measurement were the changes of CWT time and heart rate per week, musclear functino and cardiopulmonary function. The conclusions are as follows : 1. Muscular fuction 1) Back strength in SE and LE group was increased significantly (p<.01, p<.05, 8.86% and 7.08%).Grip strength was increased slightly in 4 groups but there was no significance. 2) In push-ups, all 4 groups were increased significantly (p<.05, p<.01), sit-ups also were increased significantly in SE and LE group (p<.05, 6.71% and 9.62%). 3) In SE and LE group , standing long jump was in significantly (p<.01, p<.05, 4.49% and 6.09%), but only in LE group , side step was increased significantly (p<0.1, 5.84%). 2. Cardiopulmonary function 1) HRrest was decreased slightly in all 4 groups but was not significant changes. HRmax was increased only in LE group significantly (p<.05, 2.81%), treadmill running time was increased significantly in SE and LE group respectively (p<.01, p<.05, 10.78% and 11.07%). 2) VEmax was increased significantly in SE and LE group(p<.05, p<.01, 10.59% and 13.68%), but only in LE group Rfmax was increased significantly (p<.01, 4.83%). 3) In VO2max, LCb group was increased significantly (p<.05, 6.835), but SCa group was decreased significantly (p<.05, 4.32). VO2max/kg$.$min was increased significantly in LE and LCb group respectively (p<.01 p<.05. 4.75% and 3.98%).

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.1
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• pp.43-50
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• 2004

Ischemia followed by reperfusion in the presence of polymorphonuclear leukocytes (PMNs) results in a marked cardiac contractile dysfunction. Amrinone, a specific inhibitor of phosphodiesterase 3, has an antioxidant activity against PMNs. Therefore, we hypothesized that amrinone could attenuate PMNs-Induced cardiac dysfunction by suppression of reactive oxygen species (ROS) produced fby PMNs. In the present study, we examined the effects of amrinone on isolated ischemic (20 min) and reperfused (45 min) rat hearts perfused with PMNs. Amrinone at $25\;{\mu}M$, given to hearts during the first 5 min of reperfusion, significantly improved coronary flow, left ventricular developed pressure (P<0.001), and the maximal rate of development of left ventricular developed pressure (P<0.001), compared with ischemic/reperfused hearts perfused with PMNs in the absence of amrinone. In addition, amrinone significantly reduced myeloperoxidase activity by 50.8%, indicating decreased PMNs infiltration (p< 0.001). Superoxide radical and hydrogen peroxide production were also significantly reduced in fMLP- and PMA-stimulated PMNs pretreated with amrinone. Hydroxyl radical was scavenged by amrinone. fMLP-induced elevation of $[Ca^{2+}]_i$ was also inhibited by amrinone. These results provide evidence that amrinone can significantly attenuate PMN-induced cardiac contractile dysfunction in the ischemic/reperfused rat heart via attenuation of PMNs infiltration into the myocardium and suppression of ROS release by PMNs.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.6
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• pp.1485-1496
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• 2006

Various kinds of related parameters on hypertension such as anti-oxygen effect, ACE, weight of body, hwart and kidney, blood pressure, heartbeat rates, contents of aldosterone, catecholamine, change rates, of plasma constituents, uric acid, BUN, creatinine were determined to verify the effects on hypertension by Kamisamul-tang (KSMT). And the results are concluded as follows. KSMT did not show any cytotoxicity at the range of concentration (1-250 ${\mu}g/m{\ell}$) on the human fibroblast cell (hFCs). KSMT decreased the production of reactive oxygen species (ROS) and DPPH generation depending on the concentration. KSMT significantly inhibited angiotensin converting enzyme(ACE) activity depending on the concentration compared with control. KSMT maintained body weight of body, heat and kidney nearly normal group in hypertensive rat induced by DOCA-salt. KSMT significantly blood pressure and heart beat rate compared with control in hypertensive rat induced by DOCA-salt. KSMT significantly decreased aldosterone, dopamine, norepineph- rine, epinephrine compared with control in hypertensive rat induced by DOCA-salt. KSMT significantly decreased the level of potassium and cloride compared with control wheareas increased that of calcium significantly in hypertensive rat induced by DOCA-salt. KSMT significantly decreased the level of uric acid and BUN compared with control in hypertensive rat induced by DOCA-salt. It is verified experimentally tat Kamisamultang(KMST) which has been used broadly as a clinical therapeutics in oriental medicine is effective for anti-hypertension mechanism. And it could be applied to develope the reliable prescriptions for anti-hypertension in the future.

• Journal of Ginseng Research
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• v.43 no.3
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• pp.402-407
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• 2019

Background: To investigate the neurobiological evidence supporting the adaptogenic effects of Korean Red Ginseng in reducing the harmful consequences of stress using a double-blind, placebo-controlled trial. Method: Sixty-three subjects with high stress levels were randomized to receive an orally administered, double-blind, 6-week treatment with Korean Red Ginseng (n = 32) or placebo (n = 31). All participants underwent a comprehensive psychological evaluation using Beck Depression Inventory and Stress Response Inventory, cognitive evaluation using the continuous performance test, biological evaluation by measuring blood levels of lipids, catecholamines, inflammation markers, and heart rate variability at baseline and after 6 weeks. Results: At baseline, both groups showed no significant differences in age, sex, years of education, Beck Depression Inventory, and Stress Response Inventory. After 6 weeks, triglyceride levels were significantly increased within the normal limit in the Korean Red Ginseng group (F = 4.11, p = 0.048), and the epinephrine level was decreased in this group (F = 4,35, p = 0.043). The triglyceride increase was significantly associated with epinephrine decrease (B = 0.087, p = 0.041), suggesting that Korean Red Ginseng may stabilize the sympathetic nervous system. In addition, we detected a significant group by time effect in the visually controlled continuous performance test, suggesting positive effects of Korean Red Ginseng on cognition. Conclusion: Korean Red Ginseng might help to stabilize the sympathetic nervous system and improve cognition in individuals with high stress.