• The Korean Journal of Nuclear Medicine
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• v.38 no.5
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• pp.331-337
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• 2004

Cardiac neurotransmission imaging allows in vivo assessment of presynaptic reuptake, neurotransmitter storage and postsynaptic receptors. Among the various neurotransmitter, I-123 MIBG is most available and relatively well-established. Metaiodobenzylguanidine (MIBG) is an analogue of the false neurotransmitter guanethidine. It is taken up to adrenergic neurons by uptake-1 mechanism as same as norepinephrine. As tagged with I-123, it can be used to image sympathetic function in various organs including heart with planar or SPECT techniques. I-123 MIBG imaging has a unique advantage to evaluate myocardial neuronal activity in which the heart has no significant structural abnormality or even no functional derangement measured with other conventional examination. In patients with cardiomyopathy and heart failure, this imaging has most sensitive technique to predict prognosis and treatment response of betablocker or ACE inhibitor. In diabetic patients, it allow very early detection of autonomic neuropathy. In patients with dangerous arrhythmia such as ventricular tachycardia or fibrillation, MIBG imaging may be only an abnormal result among various exams. In patients with ischemic heart disease, sympathetic derangement may be used as the method of risk stratification. In heart transplanted patients, sympathetic reinnervation is well evaluated. Adriamycin-induced cardiotoxicity is detected earlier than ventricular dysfunction with sympathetic dysfunction. Neurodegenerative disorder such as Parkinson's disease or dementia with Lewy bodies has also cardiac sympathetic dysfunction. Noninvasive assessment of cardiac sympathetic nerve activity with I-123 MIBG imaging nay be improve understanding of the pathophysiology of cardiac disease and make a contribution to predict survival and therapy efficacy.

• The Korean Journal of Physiology
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• v.29 no.2
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• pp.309-321
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• 1995

In the present study, the relationship between the somatosympathetic reflexes and arterial blood pressure responses to electrical stimulation of the peripheral nerve was investigated in cats anesthetized with ${\alpha}-chloralose$. Single sympathetic postganglionic fiber activities were recorded from the hindlimb muscle and skin nerves and also from the cervical and abdominal sympathetic chains. Effects of the morphine on responses of the sympathetic nerve and arterial blood pressure to activation of the peripheral $A{\delta}-$ and C-afferent nerves were analyzed. The following results were obtained. 1) Arterial blood pressure was depressed by peripheral AS-afferent stimulation (A-response) and was elevated during C-afferent activation (C-response). 2) Intravenously administered morphine enhanced the C-response while the A-response decreased insignificantly, Only the C-response was decreased by intrathecal morphine. 3) All the ten recorded cutaneous sympathetic fibers showed periodic discharge pattern similar to respiratory rhythm and five of them also showed cardiac-related rhythm. However, most of the muscular sympathetic fibers had cardiac-related rhythm and only four fibers showed respiratory rhythm. 4) Morphine decreased the sympathetic C-reflex elicited by the peripheral C-afferent activation and the abdominal sympathetic A-reflex was also decreased by morphine. From the above results, it was concluded that supraspinal mechanisms were involved in the enhanced arterial pressor response to peripheral C-afferent activation by intravenous morphine.

• Journal of Life Science
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• v.34 no.5
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• pp.320-332
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• 2024

The aims of this study were to compare the differences in hemodynamics between cigarette smoking and using heated tobacco products (HTPs) and to determine the acute effects of using HTPs on cardiac autonomic regulation. Another goal was to examine the acute cardiac autonomic responses when using different tobacco sticks in HTPs. Sixteen healthy male smokers completed an open-label, randomized, crossover trial consisting of non-smoking (NS), cigarette smoking, and the use of two different HTPs (IQOS with HEETS; lil SOLID with Fiit). Sub-trials, which included NS, lil SOLID with Fiit, and lil SOLID with HEET, were performed on eight smokers among the total subjects. Hemodynamic variables, such as systolic blood pressure (SBP) and diastolic blood pressure (DBP), and heart rate variability were measured before, during, and 30 minutes after using each tobacco product. Using HTPs resulted in a significant increase in both SBP and DBP, comparable to smoking cigarettes. Cardiac sympathetic activity significantly increased, and cardiac vagal tone (CVT) significantly decreased after acute exposure to HTP aerosol, similar to the effects of cigarette smoke exposure. Furthermore, differences in the withdrawal of CVT were observed when using different tobacco sticks in the same HTPs. The findings of this study indicate that acute exposure to HTP aerosol increases the hemodynamic burden and disrupts cardiac autonomic balance, similar to exposure to cigarette smoke. Moreover, depending on the type of tobacco stick inserted into the HTP device, acute withdrawal of CVT may have been enhanced.

• The Korean Journal of Physiology
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• v.6 no.2
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• pp.31-37
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• 1972

The right cervical vagus nerve was electrically stimulated for 30 sec, and 30 minutes recording cardiac rate responses and electrocardiogram. The main purposes of the present experiment are to determine effect of stimulation frequency on the maintenance of cardiac rate responses and to determine recovery time of sinus rhythm after asystole period followed by idioventricular rhythm during prolonged electrical stimulation of the vagus, and the optimal stimulation parameters for vagal stimulation were studied as well. The results obtained are summarized as follows: 1. The maximum negative chrontropic responses were obtained with the following ranges of electrical parameters. Intensity: 3V-7V, Frequency: 20/sec-60/sec, and pulse duration: 5 msec-20 msec. 2. Compared with the responses from sympathetic effectors, cardiac rate responses to electrical stimulation of vagus nerve were well maintained with all stimulation frequencies. 3. At all stimulation frequencies except 20/sec, sinus node started to take over primary pacemaker activity when cardiac rates were restored to about 38-40/min. 4. It was indicated that upper limit of idioventricular rhythm does not exceed 38-40/min. 5. With the stimulation parameter set of 20/sec-5 msec-3 V, sinus rhythm did not appear during 30 minutes of stimulation period. Therefore, this electrical parameter set appears to be optimal for elicitation of prolonged and maximum cardiac rate responses by vagal stimulation.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.3 no.1
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• pp.73-82
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• 2008

Objectives : This study was performed to examine the hypothesis that the structural imbalance affect cardiac function and autonomic reflex system and to investigate the possibility of the chiropractic care for cardiovascular system. Methods : 78 of Dong-Guk University students with structural imbalance were recruited for the investigation from March to June 2007. Heart rate variability, Buss and Durkee Hostility inventory(BDHI) and physical examinations to evaluate psoas muscle contracture were performed. Results : Left psoas muscle contracture was associated with decrease of LF/HF ratio(p=0.048). Conclusion : Left side contracture of psoas muscle showed a tendency to decrease sympathetic activity.

• Journal of Biomedical Engineering Research
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• v.17 no.1
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• pp.79-84
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• 1996

A number of experimental evidences suggest that the rnun ventrolateral medulla(RVLM) is the final common pathway in the regulation of arterial blood pressure. A Voup of neurons in the RVLM, called the cardiovascular neurons (UN), show spontaneous activity temporally synchronized with the periodic cardiac cycle. These neurons affect the sympathetic nerve discharge(SND), thus are believed to be responsible for blood pressure control. The present experiment identified 98 UVNs in 42 cats based on the temporal relationships between each neuron's activity with both the cardiac cycle and SWD. In 20 UWL changes of spontaneous firing rate(FR) during the somatosympathetic reflex(SSR) were studied Five different firing patterns were observed during the pressor and depressor responses of SSR, implying that they form an interconnected neuronal circuit interacting with one another to generate efferent signals for blood pressure regulation. In the following companion paper, the firing patterns of CVN are analyzed to develop a minimal neuronal circuit model explaining the present experimental outcome.

• Journal of Biomedical Engineering Research
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• v.17 no.1
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• pp.71-80
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• 1996

A number of experimental evidences suggest that the rnun ventrolateral medulla(RVLM) is the final common pathway in the regulation of arterial blood pressure. A Voup of neurons in the RVLM, called the cardiovascular neurons (UN), show spontaneous activity temporally synchronized with the periodic cardiac cycle. These neurons affect the sympathetic nerve discharge(SND), thus are believed to be responsible for blood pressure control. The present experiment identified 98 UVNs in 42 cats based on the temporal relationships between each neuron's activity with both the cardiac cycle and SWD. In 20 UWL changes of spontaneous firing rate(FR) during the somatosympathetic reflex(SSR) were studied Five different firing patterns were observed during the pressor and depressor responses of SSR, implying that they form an interconnected neuronal circuit interacting with one another to generate efferent signals for blood pressure regulation. In the following companion paper, the firing patterns of CVN are analyzed to develop a minimal neuronal circuit model explaining the present experimental outcome.

• The Journal of Pediatrics of Korean Medicine
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• v.27 no.3
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• pp.1-11
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• 2013

Objectives The purpose of this study is to evaluate the characteristics of autonomic nervous system in heart-weakened children via analyzing heart rate variability (HRV) compare to healthy children. Methods Among the children who have visited the department of pediatrics at OO oriental medicine hospital, the subjects were composed of 62 elementary school students without cardiac disorder, who have yet develop secondary sexual characteristics. Results 1. Mean HRT and SDNN of the heart-weakened group of children were lower than the healthy group, but with no statistical significance. 2. Heart-weakened children had higher LF norm and LF/HF ratio, but lower HF norm than healthy children. The rest of the Frequency Domain Index have no significant differences. 3. Heart-weak score showed a positive correlation with Mean HRT and LF/HF ratio. Conclusions Heart-weakened children had an imbalance in autonomic nervous system due to increase of sympathetic nerve activity and decrease of parasympathetic nerve activity.

• Journal of Multimedia Information System
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• v.5 no.2
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• pp.121-130
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• 2018

We developed multimedia esophageal catheters for use with birds to measure and record ECG and angular velocity while anesthesized, at rest, and in flight. These catheters enable estimates of blood pressure based on readings given by an angular velocity sensor and by RR intervals of ECG affected by EMG. In our experiments, the catheters had the following characteristics: 1. Esophageal catheters offer a topological advantage with 8-dB SNR improvement due to elimination of electromyography (EMG). 2. We observed a very strong correlation between blood pressure and the angular velocity of esophageal catheter axial rotation. 3. The impulse conduction pathway (Purkinje fibers) of the cardiac ventricle has a direction opposite to that of the mammalian pathway. 4. Sympathetic nerves predominate in flight, and RR interval variations are strongly suppressed. The electrophysiological data obtained by this study provided especially the state of the avian autonomic nervous system activity, so we can suspect individual's health condition. If the change of the RR interval was small, we can perform an isolation or screening from the group that prevent the pandemics of avian influenza. This catheter shall be useful to analysis an avian autonomic system, to perform a screening, and to make a positive policy against the massive infected avian influenza.

• Journal of Life Science
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• v.22 no.4
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• pp.532-537
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• 2012

We investigated the effect of smoking on cardiovascular responses during acute dynamic exercise. Eleven college students who had been smoking (duration of smoking: $7.45{\pm}0.90$ years; number of cigarettes per day: $17.72{\pm}1.22$) participated in this study. All subjects completed a graded exercise testing to determine the relative exercise intensity. The cardiovascular responses were measured at rest, and during mild and moderate exercise immediately, 24, and 48 hours after smoking. The same procedures were repeated during 24-h smoking withdrawal. All subjects were continuously instrumented to measure systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), stroke volume (SV), cardiac output (CO), and total vascular conductance (TVC) at rest and during exercise. The results showed that compared to the nicotine abstention, SBP, DBP, MAP, and HR were significantly higher at 24 and 48 hours after smoking ($p$<0.05), and CO was significantly higher at rest and during moderate exercise ($p$<0.05). There were no differences in SV and TVC before and after smoking. Thus, the results suggest that smoking is associated with an exaggerated sympathetic nerve activity during dynamic exercise. Consequently, smoking cessation may help reduce cardiac events, such as stroke and heart attack, during exercise.