• The Korean Journal of Physiology
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• v.23 no.2
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• pp.393-399
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• 1989

Sixty-seven conscious rats prepared with chronic gastric fistula were studied to examine the effect of vagotomy on gastric secretory responses to medial amygdaloid stimulation. Gastric acid output was significantly increased by electrical stimulation of the medial amygdaloid nucleus, and the increases in acid secretion were completely eliminated by vagotomy. However, in rats subjected to stimulation of the medial amygdaloid nucleus plus vagotomy, acid output was almost same as that in only vagotomized rats. And vagotomy itself decreased the acid secretion significantly. These results indicate that the influence of electrical stimulaton of the medial amygdaloid nucleus on acid secretion is carried largely via vagus nerves. And also, without electrical stimulation of medial amygdaloid nucleus, acid secretion is controlled by way of vagus in rats. Plasma gastrin concentrations were measured following stimulation of the medial amygdaloid nucleus. Plasma levels of gastrin were not significantly altered by stimulation of the medial amygdaloid nucleus with or without vagotomy. It is therefore inferred from the above results that the facilitatory influence of the medial amygdaloid nucleus on the gastric acid secretion is mediated chiefly via vagal activity and that gastrin is not responsible for the increase in acid secretion in this process.

• Journal of Acupuncture Research
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• v.20 no.1
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• pp.97-103
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• 2003

Objective : Auricular acupuncture is a method of treatment that involves needling the ear in order to produce relief of symptoms. This concept was first developed by P.Nogier, french doctor and referred to as somatotopic representation. Many authors have commented the fact that the vagus nerve supplies the external auditory and the concha. The aim of this randomised, single blind study was to investigate whether auricular acupuncture of the ear produced changes in the pulse rate, an indicator of vagal tone. Methods: 10 healthy man volunteers were divided into normal and epinephrine stimulation group. Then each group was divided into vagus area acupuncture and control area acupuncture group again. Epinephrine stimulation group was injected by epinephrine 0.3cc twice, first. All of them were needled in either the vagus area or control area of the ear, and pulse rate changes were measured by patient monitor over 1 hour. Results : In the epinephrine stimulation group, there was significant differences in the pulse rate change between vagus area acupuncture and control area acupuncture group. After injection of epinephrine, the basal pulse rate was increased 1.3~1.4 times in the control group. However, in the vagus area acupuncture group the basal pulse rate was increased only 1.1~1.2 times.

• Archives of Pharmacal Research
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• v.11 no.1
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• pp.65-73
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• 1988

The effects of clonidine on the negative chronotropic response induced by stimulation of vagus nerve were studied in the presence of propranolol in reserpinized and anesthetized rats. When the heart rate was decreased by stimulation of the vagus nerve, clonidine significantly inhibited vagally induced heart rate decrease (negative chronotropic response) in dose dependent manner. This inhibitory effect of clonidine was virtually abolished by phentolamine, ${\alpha}_1-\;and\;{\alpha}_2-adrenoceptor$ antagonist, and partially antagonized by prazosin, ${\alpha}_1-adrenoceptor$ antagonist. On the other hand, when the heart rate was decreased by the infusion of bethanechol, a muscarinic parasympathetic stimulant, clonidine had no effect on the bethanechol-induced heart rate decrease. These results suggest that clonidine inhibits vagally induced negative chronotropic response by activation of presynaptic ${\alpha}-adrenoceptors$ located on the parasympathetic cholinergic nerve terminal in the heart and this effect of clonidine is more related to ${\alpha}_2-adrenoceptors$ than ${\alpha}_1-adrenoceptors$.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2000.11a
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• pp.81-87
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• 2000

Beat-to-beat changes in heart period (heart period variability, HPV) are mediated by fluctuations in autonomic activity. Spectral analysis is used to quantify such fluctuations in the range of 0.15-0.40 Hz (high frequency, HF), which are influenced primarily by parasympathetic factors. These fluctuations are often referred to as RSA (respiratory sinus arrhythmia), the physiological phenomenon extracted by spectral analysis and other methods including histograms of heart rate ( HR), deviations of HR etc. Respiratory sinus arrhythmia indexing with peak-to-valley method suggested by Grossman et at., (1981) yields a simple range statistic and is quantified on breath-by-breath basis, thus being quite sensitive and less dependent on recording time as compared to spectral analysis. It is strongly recommended to use at least 1 min epoch to asses HF component of HPV and at least 2 min fer low frequency (LF) of HPV and even 5 min far valid clinical assessment. Peak-to-valley statistic is limited to RSA index only, but has its pragmatic advantages. Most important is possibility of its application far relatively small epoch analysis. We used short periods (20,30, 40 sec only) and off-line analysis of RSA using ECG and respiration curve this method of assessment and proved that this method is more practically effective. The RSA index was not so far dependent on respiration pattern differences and reflected actual vagal control of HR and were accompanied by low HR under some high stress conditions and in an aversive affective visual stimulation experiments. Another factor that might modulate cardiac chronotropic response is the interaction of sympathetic and parasympathetic inputs on sino-atrial (SA) node level, because responses to vagal influences are known to be proportional to ongoing sympathetic activity, that is so called accentuated antagonism. Since sympathetic outflow (increment of influences on SA) under negative emotions or stress was high in almost all physiological responses, vagal effects on HR could be therefore potentiated, leading to masking of output cardiac response seen in HPV, In the case of moderate sympathetic activation, on the other hand, autonomic interactions in cardiac control appear to be minimal. Thus RSA index appears to be an effective alternative method to assess and measure spectral HPV.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1998.11a
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• pp.225-229
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• 1998

The purpose of the current study was comparative analysis of autonomic and electrocortical responses to passive and active touch of the tektites with different subjective emotional preference. Perspective goal of the project is development of a template for classification of tactile stimuli according to subjective comfort and associated physiological manifestations. The study was carried out on 36 female college students. Physiological signals were acquired by Grass and B10PAC 100 systems with AcqKnowledge III software. Frontal, parietal and occipital EEG (relative power spectrum /percents/ of EEG bands - delta, theta, slow and fast alpha, low and fast beta), and autonomic variables, namely heart rate (HR), respiratory sinus arrhythmia (RSA), pulse transit time (PTT), respiration rate (RSP) and skin conductance parameters (SCL, amplitude, rise time and number of SCRs) were analyzed for rest baseline and stimulation conditions. Analysis of the overall pattern of reaction indicated that autonomic response to tactile stimulation was manifested in a form of moderate HR acceleration, RSP increase, RSA decrease (lowered vagal tone), decreased n and increased electrodermal activity (increased SCL, several SCRs) that reflects general sympathetic activation. Parietal EEG effects (on contra-lateral side to stimulated hand) were featured by short-term alpha-blocking, slightly reduced theta and significantly increased delta and enhanced fast beta activity with few variations across stimuli. The main finding of the study was that most and least preferred textures exhibited significant differences in autonomic (HR, RSP, PTT, SCR, and at less extent in RSA and SCL) and electrocortical responses (delta, slow and fast alpha, fast beta relative power). These differences were recorded both in passive and active stimulation modes, thus demonstrating reproducibility of distinction between most and least emotionally preferred tactile stimuli, suggesting influence of psychological factors, such as emotional property of stimulus, on physiological outcome. Nevertheless, development of sufficiently sensitive .and reliable template for classification of emotional responses to tactile stimulation based on physiological response pattern may require more extensive empirical database.

• Archives of Pharmacal Research
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• v.12 no.4
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• pp.243-248
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• 1989

Effects of B-HT 920 on the vagally stimulated gastric acid secretion were studied in anesthetized and gastric fistula rats. When the gastric acid secretion was increased by stimulation of the vagus nerve, B-HT 920 was partially attenuated by prazosin, $\alpha_1-$adrenoceptor antagonist and virtually abolished by yohimbine, $\alpha_2-$adrenoceptor antagonist. On the other hand, when the gastric acid secretion was increased by the infusion of bethanechol, a muscarinic parasympathetic stimulant, B-HT 920 had no effect on the bethanechol-induced gastric acid secretion. These results suggest that B-HT 920 inhibits vagally induced gastric acid secretion by activation of presynaptic $\alpha-$adrenoceptors located on the vagally stimulated pathways in the gastric wall and this effect of B-HT 920 is more related to $\alpha_2-$adrenoceptors than $\alpha_1-$adrenoceptors.

• Science of Emotion and Sensibility
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• v.1 no.2
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• pp.13-22
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• 1998

The sense of touch has both objective and subjective characteristics. During hand evaluation of the fabrics. psycho physiological processes such as emotion and stimulation. On other site, the mode of touch (passive vs. active) is also capable to modulate somatosensory responses. I.e., suppress somatocensory perception during active electrocortical responses to passive and active touch of the textiles with different subjective emotional preference. The study was carried out on 36 female college students. Physiological signals were acquired by Grass and BIOPAC 100 systems with AcqKnowledge variables, namely heart rate (HR), respiratory sinus arrhythmia (RSA), pulse transit time (PTT), respiration rate (RSP) and skin conductance parameters (SCL, amplitude, risetime and number of SCRs) were analyzed for baseline and stimulation conditions. Analysis was manifested in a form of moderate HR acceleration. RSP increase, RSA decrease (lowered vagal tone), decreased PTT and increased electrodermal activity (increased SCL, several SCRs) that reflects general sympathetic activation. Parietal EEG effects (on contra-lateral side to stimulated hand)were featured by short-term alpha-blocking, slightly reduced theta, significantly increased delta and enhanced fast beta activity with few variations across stimuli. The main finding of the study was that most and least preferred textures exhibited significant differences in autonomic (HR, RSP, PTT, SCR, and at less extent in RSA and SCL) and electrocortical responses (delta, slow and fast alpha, fast beta relative power). These differences were recorded both in passive and active stimulation modes, thus demonstrating reproducibility of distinction between most and least emotionally preferred tactile stimuli, suggesting influence of psychological factors, such as emotional property of stimulus, on physiological outcome.

• Journal of Korean Medicine Rehabilitation
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• v.34 no.1
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• pp.65-81
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• 2024

Objectives This study aimed to understand the general research trends, applicated disease, and methodology of transcutaneous/percutaneous vagus nerve stimulation, contemplating its clinical use in traditional Korean medicine and future research directions. Methods A scoping review was conducted following Arksey and O'Malley Framework Stage and adhering to the PRISMA extension for scoping reviews: checklist and explanation. Papers published until October 30, 2023, were investigated across 10 databases (PubMed, Embase, Scopus, Web of Science, China National Knowledge Infrastructure, Oriental Medicine Advanced Searching Integrated System, Korean Studies Information Service System, KMbase, Science ON, Research Information Sharing Service. The search terms used were 'Transcutaneous/Percutaneous vagus nerve stimulation'. Results Since 2021, the application of transcutaneous/percutaneous vagus nerve stimulation for musculoskeletal symptoms has been actively researched, predominantly in Asia (37%), Europe (37%), and North America (21%). All 19 papers were part of clinical studies. Chronic pain was noted that most applied disease, it also was found to potentially aid in acute post-surgical pain relief. Major assessment tools include not only simple pain metrics but also pain perception, vagal nerve tension, quality of life, and inflammatory markers. Most procedures were carried out through the ear, which offers a favorable site for therapeutic stimulation without notable side effects. And parameter analysis, frequencies typically ranged around 25 Hz to 30 Hz, while pulse widths were commonly set at 250 ㎲ or 300 ㎲. Conclusions Transcutaneous/percutaneous vagus nerve stimulation is easily accessible through acupuncture in Korean medicine. Therefore, if future studies establish parameters and clinical significance, it could be utilized as a therapeutic modality.

• Korean Journal of Veterinary Research
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• v.30 no.3
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• pp.277-281
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• 1990

Xylazine is commonly used for anesthesia in veterinary medicine and various adverse effects are developed. To examine if the severe hypotensive response associated with xylazine-induced anesthesia might be resulted from the stimulation of presynaptic alpha-2 adrenoceptors or the increase of vagal tone, effects of yohimbine, atropine and atropine with vagotomy on xylazine-induced severe and long-lasting hypotensive responses were investigated in rabbits. The results were summarized as follows: 1) Intravenously injected xylazine(1mg/kg)-induced hypotensive responses were inhibited by yohimbine(p<0.001). 2) Intravenously injected xylazine(1mg/kg)-induced hypotensive responses were not changed by atropine. 3) Intravenously administered xylazine(1mg/kg)-induced hypotensive responses are not changed by atropine with vagotomy. These results indicate that xylazine is thought to cause severe hypotensive response during anesthesia primarily by stimulating presynaptic alpha-2 adrenoceptors and other receptors or mechanisms may participate in the hgpotensive response of xylazine.

• Journal of The Korean Society of Clinical Toxicology
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• v.13 no.2
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• pp.111-116
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• 2015

Veratrum patulum has toxicological relevance because of the potential for misidentification of this plant as mountain garlic. Veratrum patulum has an ester-alkaloid that provokes cardiac arrhythmias by excessive vagal stimulation and depression of the sinoatrial and atrioventricular nodes of the heart and hypotension, cardiomegaly. We report on a retrospective case of successful outcome in patients with veratrum patulum poisoning through active treatment from the early phase after ingestion. We report on a case involving a patient who experienced dizziness, dyspnea, hypotension, and elevation of cardiac enzyme, cardiomegaly. These cases were kept under observation and generally recovered with supportive care. We report on cases of veratrum patulum poisoning with review of literature.