Changes in gap junction proteins Connexin30. 2 and Connexin40 expression in the sinoatrial node of rats with dexmedetomidine-induced sinus bradycardia

Abstract Background Dexmedetomidine (Dex) is widely used, and its most common side effect is bradycardia. The complete mechanism through which Dex induces bradycardia has not been elucidated. This research investigates the expression of gap junction proteins Connexin30.2 (Cx30.2) and Connexin40 (Cx40) within the sinoatrial node of rats with Dex-induced sinus bradycardia. Methods Eighty rats were randomly assigned to five groups. Saline was administered to rats in Group C. In the other four groups, the rats were administered Dex to induce bradycardia. In groups D1and D2, the rats were administered Dex at a loading dose of 30 μg.kg−1 and 100 μg.kg−1 for 10 min, then at 15 μg.kg−1.h−1 and 50 μg.kg−1.h−1 for 120 min separately. The rats in group D1A and D2A were administered Dex in the same way as in group D1and D2; however, immediately after the administration of the loading dose, 0.5 mg atropine was administered intravenously, and then at 0.5 mg.kg−1.h−1 for 120 min. The sinoatrial node was acquired after intravenous infusion was completed. Quantitative real-time polymerase chain reaction and western blot analyses were performed to measure mRNA and protein expression of Cx30.2 and Cx40, respectively. Results The expression of Cx30.2 increased, whereas the expression of Cx40 decreased within the sinoatrial node of rats with Dex-induced sinus bradycardia. Atropine reversed the effects of Dex on the expression of gap junction proteins. Conclusion Dex possibly altered the expression of gap junction proteins to slow down cardiac conduction velocity in the sinoatrial node.

Correlation Study Between Synchronic Heart Rate Variability, Blood Pressure Variability and Blood Vessel Damage in Patients With Essential Hypertension / 中国循环杂志

Objective: To investigate the relationship between heart rate variability (HRV), blood pressure variability (BPV) and autonomic nerve function, blood vessel damage in patients with essential hypertension (EH) via synchronous monitoring. Methods: A total of 275 EH patients admitted to our hospital from 2011-04 to 2014-01 were enrolled. The vascular function was assessed by carotid-femoral pulse wave velocity (PWV). Based on PWV, the patients were divided into 2 groups: Normal PWV group (PWV<9m/s),n=185 and High PWV group (PWV≥9m/s),n=90. Synchronic 24h dynamic electrocardiogram (Holter) and 24h ambulatory blood pressure monitoring (ABPM) were performed in all patients. t-test, chi-square test, person liner correlation study and multi stepwise regression analysis were conducted to explore the relationship between HRV, PBV and PWV. Results: HRV and BPV in High PWV group had been changed unusually. Compared with Normal PWV group, High PWV group showed decreased standard deviation of the average of all normal-to-normal intervals in all 5-minute intervals (SDANN) (159.66±66.50) ms vs (194.36±119.29) ms and increased 24 h systolic blood pressure standard deviation (24h SSD) (14.40±3.65) mmHg vs (12.98±3.46) mmHg, all P<0.01; increased new index of night/day HR ratio (0.90±0.08) vs (0.87±0.06), P<0.01 and it had liner correlation to PWV (r=0.169, P=0.005). Multi stepwise liner regression analysis indicated that 24hSSD and HRV at low frequency (LF) portion had obvious and independent correlation to PWV (standard β value=0.352 and 0.212 respectively). Conclusion: ① EP patients were with decreased HRV (SDANN), increased BPV (24h SSD) and the higher incidence of arteriosclerosis; 24h SSD and HRV at LF portion were the most 2 important risk factors affecting PWV. ②Autonomic nerve dysfunction, vagus nerve over-excitatory were the independent risk factors for promoting the occurrence and development of arteriosclerosis in EH patients. ③Night/day HR ratio as a sensitive index for examining autonomic nerve function was independently related to hypertensive vessel damage. Synchronic monitoring of HRV and BPV is helpful to identify blood vessel damage in EH patients.

Another Understanding for Effects of Physical Stimuli on Modification of Autonomic Nerve System by Two Kinds of Stimuli on Feet / 日本温泉気候物理医学会雑誌

Background: In one series of studies, we observed the effects of acupuncture treatment (AT) on the autonomic nerve system (ANS). We experimented from various view-points. At last, we discovered a specific pattern for modifying ANS status, which showed that functions of the parasympathetic nerve increased while those of the sympathetic nerve decreased. To further study systematic modification of ANS balance, we focused on the lower body (feet). Moreover, two kinds of stimuli, tapping and vibration, were applied while measuring the value of finger floor distance (FFD) and heart rate (HR). Finally, the effects on ANS were discussed. Methods: Twenty healthy subjects participated in this study, and they were divided into two groups; the tapping group and the vibration group. The former received 50 taps on the feet, and the latter received vibrations for two minutes. In order to indicate ANS status the effects of these stimuli were evaluated by FFD values and a kinetic record of changes in HR. Results: Both groups showed improvement in FFD values, which was the same as the results for AT via modification of ANS. However, changes in HR showed a different pattern from AT; in this study sympathetic nerve) dominantly showed an increase without a decrease in parasympathetic nerve. Discussion and Conclusions: The reasons for differences in ANS modification may be found in the role, especially in an emergency, of the lower body. The lower body is heavy in skeletal muscles, which needs energy and blood to react during acute stress. The ANS, which controls blood distribution, may shift and concentrate system blood from the smooth muscles of the stomach (controlled by parasympathetic nerve) to the skeletal muscles of the legs and feet (controlled by sympathetic nerve). Thus, this study indicated that local stimuli of the foot induced systematic ANS modification.

Another Understanding for Effects of Physical Stimuli on Modification of Autonomic Nerve System by Two Kinds of Stimuli on Feet / 日本温泉気候物理医学会雑誌

<b>Background:</b> In one series of studies, we observed the effects of acupuncture treatment (AT) on the autonomic nerve system (ANS). We experimented from various view-points. At last, we discovered a specific pattern for modifying ANS status, which showed that functions of the parasympathetic nerve increased while those of the sympathetic nerve decreased. To further study systematic modification of ANS balance, we focused on the lower body (feet). Moreover, two kinds of stimuli, tapping and vibration, were applied while measuring the value of finger floor distance (FFD) and heart rate (HR). Finally, the effects on ANS were discussed.<BR><b>Methods:</b> Twenty healthy subjects participated in this study, and they were divided into two groups; the tapping group and the vibration group. The former received 50 taps on the feet, and the latter received vibrations for two minutes. In order to indicate ANS status the effects of these stimuli were evaluated by FFD values and a kinetic record of changes in HR.<BR><b>Results:</b> Both groups showed improvement in FFD values, which was the same as the results for AT via modification of ANS. However, changes in HR showed a different pattern from AT; in this study sympathetic nerve) dominantly showed an increase without a decrease in parasympathetic nerve.<BR><b>Discussion and Conclusions:</b> The reasons for differences in ANS modification may be found in the role, especially in an emergency, of the lower body. The lower body is heavy in skeletal muscles, which needs energy and blood to react during acute stress. The ANS, which controls blood distribution, may shift and concentrate system blood from the smooth muscles of the stomach (controlled by parasympathetic nerve) to the skeletal muscles of the legs and feet (controlled by sympathetic nerve). Thus, this study indicated that local stimuli of the foot induced systematic ANS modification.

Higher QT Dispersion in Patients with Social Anxiety Disorder

OBJECTIVES: Social phobia is frequently accompanied with autonomic nerve system symptoms. QT dispersion( QTd) is the maximum inter-lead difference in QT interval, an indicator of the autonomic nerve system( ANS) disparity of the heart itself. The objective of this study is to investigate the ANS disparity, which is measured by QTd, is associated with pathophysiology of social phobia. METHODS: This research have compared QT dispersion of 25 physically healthy social phobia outpatients(16 men, 9 women, the average age 35.5 +/- 12.9) and age and sex matched control group of mentally and physically healthy 25 volunteers(16 men, 9 women, the average age 34.83 +/- 12.7). QTd was measured by previously described method. RESULTS: QTd and rate-corrected QTd were significantly higher on the patient group than the control group[QTd(patients vs. controls : 52.60 +/- 27.63ms vs. 27.53 +/- 14.29ms, p<0.0001), QTd(patients vs. controls : 55.79 +/- 27.98ms vs. 29.10 +/- 14.24ms, p<0.0001)]. CONCLUSION: Our study showed that the patients with social phobia have higher QTd than the normal controls. These results suggest that the ANS disparity, which is measured by QTd, is associated with pathophysiology of social phobia.

Disorder of Autonomic Nervous System in Stroke Patients by Local Perspiration Meters and Accelerated Photoplethymography / 日本温泉気候物理医学会雑誌

 Shoulder hand syndrome was one of the severe complications in stroke patients and often disturbed the QOL and the rehabilitation therapy. The reflex sympathetic dystrophy (RSD) was considered as the pathogenesis of shoulder hand syndrome, but the therapy had been not established. We analyzed the sympathetic nerve function of thermotherapy of shoulder-neck or passive exercise of limbs in stroke patients. ‹methods› In stoke patients suffering from shoulder hand syndrome, we set the thermisters (Terumo.Co. CMT-205) and local perspiration meters (Skinos Co. SKD 2000) on both forefingers and set the accelerated photoplethysmography (Tokyo Iken Co. SA.3000P). We analyzed the blood vessel tension (BVT) and the wave type. ‹results› The temperature of the paralytic fingers and hands was significantly higher than the temperature of the normal sides. The pulse wave patterns and blood vessel tension in paralytic fingers were more disturbed than those of intact fingers. The perspirations of paralytic hands were significantly correlated with duration and systolic blood pressures and the sympathetic nerve function was considered to concern to the disorders in early stage of stoke.

Effect of Automatic Nervous System and Personality on Stress-induced Arrhythmias(review) / 中国康复理论与实践

@#There are many factors which can affect the genesis and prognosis of the stress-induced arrhythmias,besides the automatic nerve system,the personality,central nervous system and hereditary factors have been involved.It is very important to comprehend the relationship and effects of these factors for prevention of stress-induced arrhythmias.

Changes in Heart Rate Variability after Weight Reduction in the Obese

BACKGROUND: Obesity increases morbidities and mortalities due to cardiovascular diseases. In previous studies, decrease in heart rate variability was associated with cardiovascular death and reduced heart rate variability in the obese had been reported. The authors investigated immediate changes in the heart rate variability after weight reduction in obese individuals. METHODS: The subjects for this study were 39 Korean adults (35 female, 4 male), who visited obesity clinic in a university hospital from January 2002 to July 2003. At first visit, weight, height, body mass index (BMI) and waist circumference of the subjects were measured. We also measured parameters of heart rate variability: Mean Heart Rate (MHR), Standard Deviation of N-N interval (SDNN), The Square Root of the Mean Squared Difference of successive NN intervals (RMSSD), Total Power (TP), Low Frequency (LF), High Frequency (HF), and LF/HF ratio. Weight reduction protocol included nutritional counseling, exercise, behavioral modification and anti-obesity medications, if needed. RESULTS: At 12 weeks of intervention, weight, BMI, waist circumference, fat mass, and lean body mass significantly decreased (3.90+/-3.11 kg, -1.50+/-1.21 kg/m2, -4.45+/-5.61 cm, -3.03+/-2.45 kg, -1.32+/-1.16 kg, P <0.01, respectively). MHR (-6.17+/-9.65 bpm, P <0.01) and LF/ HF (-0.61+/-1.56, P <0.05) showed significant reduction. Changes of weight and LF were positively correlated (r=0.338, P <0.01). Changes of waist circumference was correlated with changes of SDNN (r= 0.331, P <0.05). Changes of BMI showed positive correlation with changes in TP (r=0.327, P <0.05) and LF (r=0.345, P <0.05). CONCLUSION: Short term intervention for obese people decreased sympathetic nervous activity.

Dynamic changes and significance of heart rate variability during the initial phase of acute Tibet plateau exposure / 第三军医大学学报

Objective To explore the dynamic changes and significance of heart rate variability(HRV)during the initial phase after acute exposure to Tibet plateau by combining time,frequency domain and non-linear analysis.Methods Eighty-six healthy young men of Han nationality underwent short-term(5 min)heart rate variability(HRV)monitoring at 560 meter above sea level(plain),then were transported to Tibet plateau(3675-meter above sea level)by airplane.There,all subjects were divided into 3 groups,and A gorup(n=12)underwent HRV monitoring on the 2nd day after arrival,B group(n=48)on the 3rd day,C group(n=26)on the 4th day.Results Compared with the data obtained at plain,the standard deviation of normal to normal intervals(SDNN),high frequency(HF)and total power(TP)decreased significantly(P50 ms(PNN50)and normalized high frequency(HFnu)also decreased obviously(P

Comparison of T2 Sympathetic Block Effects on Blood Pressure and Heart Rate by Clipping and Sympathicotomy / 대한마취과학회지

BACKGROUND: Thoracoscopic sympathicotomy was, at first, thought to be a simple and safe method for treatment of hyperhydrosis. However, the main disadvantage of this procedure is irreversibility in additions so-called rebound sweating occurred in 30 40% of patients during the first 1 2 weeks after operation. Some patients regret the surgery, even to the extend of preferring the original sweaty hands. Recently clipping has been suggested one of the way to minimize such problem. Hypothesis of this study was that sympathetic nerve block effect by clipping may be weak compared to sympathicotomy. The aim of this study was to evaluate and compare the sympathicotomy by clipping effect on cardiovascular system. METHODS: Sixty-five patients with essential hyperhydrosis in ASA physical status class 1 undergoing thoracoscopic sympathetic block were randomly divided into two groups: The Clipping group (N = 21) and the sympathicotomy (N = 44) group. Anesthesia was induced with thiopental sodium (5 mg/kg) and pancuronium (0.05 mg/kg) and maintained with enflurane. The operation was done to the left side first and the to the right by an experienced surgeon. During the procedure, we measured blood pressure using a non invasive technique at the right forearm, heart rate and temperature after anesthetic induction as baseline values, immediately after the left side resection of the T2 sympathetic trunk or clipping, and after completely both sides resection. All the records were coded and analysed single blind by one author. RESULTS: After the T2 sympathicotomy, heart rate decreased from 87 +/- 14 to 76 +/- 17 (P < 0.05) and the mean blood pressure was reduced from 77 +/- 14 to 64 +/- 10 mmHg (P < 0.05). After T2 clipping, heart rate decrease from 88 +/- 18 to 73 +/- 14 (P < 0.05) and mean blood pressure was reduced from 74 +/- 12 to 67 +/- 13 mmHg (P < 0.05). CONCLUSION: The main result of this study was that there was no significant difference in sympathetic block effects on blood pressure and heart rate between clipping and sympathicotomy during the procedure.

The long-term effect of percutaneous coronary intervention on cardiac autonomic nerve system / 重庆医科大学学报

Objective:To investigate the long effect of pereutaneous coronary intervention(PCl)on heart rate variability(HRV) in patients with coronary artery disease(CAD),and to evaluate the prognosis of patients with CAD receiving PCI.Methods:To choose 32 patients confirmed by coronary arteriography and suitable for PCl,and to choose 32 control patients with non-CAD confirmed by coronary arteriography,HRV indices were analyzed hefore PCI and Iweek,Imonth,3months,6months,lyear after PCI.Results:HRV indices were decreased in patients with CAD,HRV was lower in patients in lweek after PCI than that before PCI,HRV was gradually increased in lmonth and there was significantly improved in 6months after PCI,and nearly to the level of control group in one year.Conclusion:HRV is low in the patients with CAD,there is slightly decreased in the early stage of PCl,but the long effect of PCI on heart rate variability can be observed.

The role of autonomic nerve system in the pathogenesis of acute mountain sickness / 解放军医学杂志

Objective To investigate the role of autonomic nerve system(ANS)in the pathogenesis of acute mountain sickness(AMS).Methods A hypobaric chamber was used to simulate 4500m altitude for 1 day.The function of ANS of 43 healthy young males was measured individually before the experiment,and then at a “height” of 4500m for 5min.GJB1098-91 clinical questionnaires were conducted to evaluate the AMS symptomatic scores.HRV was measured respectively before the test and 2h,10h,20h at 4500m;cold pressure test(CPT)and plasma concentration of NA were determined before the test and at 4500m,AMS scores were evaluated at the end of exposure.25 subjects with AMS scores of 10 or less were identified as mild AMS group(group A),and another 18 subjects with scores of over 10 were gathered as moderately severe AMS group(group B).Results Compared with group A,the systolic pressure(SP)during CPT increased markedly in group B(P