• 제목/요약/키워드: Cardiac activity

검색결과 373건 처리시간 0.027초

2K1C 고혈압(高血壓) 백서(白鼠)의 모델에 대한 심실(心實),신실증( 腎實證) 오행(五行) 사법(瀉法) 자침(刺鍼)이 혈압(血壓) 및 혈장(血漿) Renin, ANP에 미치는 영향(影響) (The effects of reduction of acupuncture techniques of five evolutive phase for appling excess in the heart, kidney on blood pressure, cardiac hypertrophy, plasma renin and ANP in hypertensive rat induced by two kidney one clip)

  • 윤대환;왕국환;한정희;박현정;나창수
    • Korean Journal of Acupuncture
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    • 제22권1호
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    • pp.75-84
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    • 2005
  • Objectives : Acupuncture has been used as treatment of disease in the korean medicine. In this study, it was investigated that effects of reduction of acupuncture techniques of five evolutive phase for appling excess in the heart, kidney on cardiovascular system as blood pressure and renin and atrial natriuretic peptide (ANP) in plasma, cardiac hypertrophy. Materials and methods : The experiments were performed on Sprague Dawley rats, 2K1C hypertension model was prepared by constricting the left renal artery with a sliver clip. Animals were then divided into seven groups, 2K1C induced and no treated group (Control), acupuncture on SP3 HT7(AC-1), LR1 KI1 (AC-2), SP3 HT7 LR1 KI1 (AC-3). The treatments were performed once a day for 10 days in rats. Results : The results are that the blood pressure was significantly decreased at 15days in AC-1 group. The cardiac hypertrophy was significantly decrease in AC-3 group. The activity of plasma ANP was increased in all groups without AC-1 group and the that of plasma Rein was decrease in AC-1, AC-2 groups than control group. Conclusions : These results suggest that acupuncture at SP3 HT7 and SP3 HT7 LR1 KI1 can be used as a therapy for controlling renal hypertension induced by 2K1C in the rats.

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베타1-아드레날린 수용체를 표적으로 하는 심근영상제로서 18F 표지된 nebivolol의 합성 (Synthesis of [18F]-Labelled Nebivolol as a β1-Adrenergic Receptor Antagonist for PET Imaging Agent)

  • 김택수;박정훈;이준영;양승대;장동조
    • 방사선산업학회지
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    • 제10권4호
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    • pp.181-187
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    • 2016
  • Selective ${\beta}_1$-agonist and antagonists are used for the treatment of cardiac diseases including congestive heart failure, angina pectoris and arrhythmia. Selective ${\beta}_1$-antagonists including nebivolol have high binding affinity on ${\beta}_1$-adrenergic receptor, not ${\beta}_2$-receptor mainly expressed in smooth muscle. Nebivolol is one of most selective ${\beta}_1$-blockers in clinically used ${\beta}_1$-blockers including atenolol and bisoprolol. We tried to develop clinically useful cardiac PET tracers using a selective ${\beta}_1$-blocker. Nebivolol is $C_2$-symmetric and has two chromane moiety with a secondary amino alcohol and aromatic fluorine. We adopted the general synthetic strategy using epoxide ring opening reaction. Unlike formal synthesis of nebivolol, we prepared two chromane building blocks with fluorine and iodine which was transformed to diaryliodonium salt for labelling of $^{18}F$. Two epoxide building blocks were readily prepared from commercially available chromene carboxylic acids (1, 8). Then, the amino alcohol building block (15) was prepared by ammonolysis of epoxide (14) followed by coupling reaction with the other building block, epoxide (7). Diaryliodonium salt, a precursor for $^{18}F$-aromatic substitution, was synthesized in moderate yield which was readily subjected to $^{18}F$-aromatic substitution to give $^{18}F$-labelled nebivolol.

Relation of Various Parameters Used to Estimate Cardiac Vagal Activity and Validity of pNN50 in Anesthetized Humans

  • Lee, Jae Ho;Huh, In Young;Lee, Jae Min;Lee, Hyung Kwan;Han, Il Sang;Kang, Ho Jun
    • 고신대학교 의과대학 학술지
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    • 제33권3호
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    • pp.369-379
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    • 2018
  • Objectives: Analysis of heart rate variability (HRV) has been used as a measure of cardiac autonomic function. According to the pNN50 statistic, the percentage of differences between successive normal RR intervals (RRI) that exceed 50 ms, has been known to reflect cardiac vagal modulation. Relatively little is known about the validity of pNN50 during general anesthesia (GA). Therefore, we evaluated the correlation of pNN50 with other variables such as HF, RMSSD, SD1 of HRV reflecting the vagal tone, and examined the validity of pNN50 in anesthetized patients. Methods: We assessed changes in RRI, pNN50, root mean square of successive differences of RRI (RMSSD), high frequency (HF) and standard deviation 1 (SD1) of $Poincar{\acute{e}}$ plots after GA using sevoflurane anesthesia. We also calculated the probability distributions for the family of pNNx statistics (x: 2-50 ms). Results: All HRV variables were significantly decreased during GA. HF power was not correlated with pNN50 during GA (r = 0.096, P = 0.392). Less than pNN47 was shown to have a correlation with other variables. Conclusions: These data suggest that pNN50 can not reflect the level of vagal tone during GA.

The WNT/Ca2+ pathway promotes atrial natriuretic peptide secretion by activating protein kinase C/transforming growth factor-β activated kinase 1/activating transcription factor 2 signaling in isolated beating rat atria

  • Li, Zhi-yu;Liu, Ying;Han, Zhuo-na;Li, Xiang;Wang, Yue-ying;Cui, Xun;Zhang, Ying
    • The Korean Journal of Physiology and Pharmacology
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    • 제26권6호
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    • pp.469-478
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    • 2022
  • WNT signaling plays an important role in cardiac development, but abnormal activity is often associated with cardiac hypertrophy, myocardial infarction, remodeling, and heart failure. The effect of WNT signaling on regulation of atrial natriuretic peptide (ANP) secretion is unclear. Therefore, the purpose of this study was to investigate the effect of Wnt agonist 1 (Wnta1) on ANP secretion and mechanical dynamics in beating rat atria. Wnta1 treatment significantly increased atrial ANP secretion and pulse pressure; these effects were blocked by U73122, an antagonist of phospholipase C. U73122 also abolished the effects of Wnta1-mediated upregulation of protein kinase C (PKC) β and γ expression, and the PKC antagonist Go 6983 eliminated Wnta1-induced secretion of ANP. In addition, Wnta1 upregulated levels of phospho-transforming growth factor-β activated kinase 1 (p-TAK1), TAK1 banding 1 (TAB1) and phospho-activating transcription factor 2 (p-ATF2); these effects were blocked by both U73122 and Go 6983. Wnta1-induced ATF2 was abrogated by inhibition of TAK1. Furthermore, Wnta1 upregulated the expression of T cell factor (TCF) 3, TCF4, and lymphoid enhancer factor 1 (LEF1), and these effects were blocked by U73122 and Go 6983. Tak1 inhibition abolished the Wnta1-induced expression of TCF3, TCF4, and LEF1 and Wnta1-mediated ANP secretion and changes in mechanical dynamics. These results suggest that Wnta1 increased the secretion of ANP and mechanical dynamics in beating rat atria by activation of PKC-TAK1-ATF2-TCF3/LEF1 and TCF4/LEF1 signaling mainly via the WNT/Ca2+ pathway. It is also suggested that WNT-ANP signaling is implicated in cardiac physiology and pathophysiology.

일회성 등속성 운동이 심장 자율신경 조절 및 근속성에 미치는 영향 (Effect of Transient Isokinetic Exercise on Cardiac Autonomic Nervous Modulation and Muscle Properties)

  • 박수경;박시은
    • 대한통합의학회지
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    • 제11권4호
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    • pp.27-39
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    • 2023
  • Purpose : The aim of this study was to identify the influence of transient isokinetic exercise on cardiac autonomic modulation and muscle properties in healthy male subjects. Methods : Twenty-eight healthy males underwent isokinetic exercise of both knee joints using a Biodex systems 3 isokinetic dynamometer with an angular velocity of 60 °/sec. The changes in activity of the autonomic nervous system, as determined by heart rate variability (HRV), and in muscle properties were evaluated at three times: pre-exercise, immediately post-exercise, and 10 min post-exercise. Results : The time domain analysis of HRV revealed significant changes in the beat count and mean and minimal heart rate (HR) measured at pre-exercise, immediately post-exercise, and 10 min post-exercise (p<.001). The beat count and mean HR were markedly increased immediately post-exercise compared to pre-exercise, but then significantly decreased at 10 min post-exercise (p<.001). All parameters of the frequency domain were significantly altered by isokinetic exercise (p<.01). The low frequency/high frequency (LF/HF) ratio, as an index for the sympathovagal balance, was elevated by exercise and remained at a similarly high level at 10 min post-exercise (p<.01). The muscle properties of rectus femoris were changed as follows: Muscle tone and stiffness were significantly increased between pre-exercise and immediately post-exercise (p<.001), and between pre-exercise and at 10 min post-exercise (p<.001). Whereas, the elasticity showed no significant change. Conclusion : These results demonstrated that transient isokinetic exercise could induce changes in cardiac autonomic control and muscle properties. In particular, up-regulation of LF/HF ratio after exercise signifies thus enhanced sympathetic modulation by isokinetic exercise. Therefore, it is needed to understand the cardiovascular risks that may arise during isokinetic exercise for providing the basic evidence to establish appropriate isokinetic exercise protocols as effective rehabilitation exercises.

Altered Cardiac $Na^{+}$,$K^{+}$-ATPase Activity in Prehypertensive Spontaneously Hypertensive Rat

  • Lee, Shin-Woong-;Lee, Jeung-Soo-
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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    • pp.300-300
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    • 1994
  • $Na^{+}$,$K^{+}$-ATPase activity, $Na^{+}$-dependent phosphorylalion, and [$^3$〕ouabain binding in sarcolemma prepared from 4 week old spontaneously hypertensive rat(SHR) ventricles were compared to the same parameters in sarcolemma from age matched normotensive Wistar-Kyoto(WKY) rat ventricles to examine whether the reduced myocardial $Na^{+}$-pump activity in SHR is an inherited enzymatic defect or a second phenomenon due to sustained hypertension. The total body weights, ventricular weights, and blood pressures were the same for SHR and WKY. No significant differences in sarcolemmal protein content and protein recovery were noted between the two pups. Sarcolemma isolated from SHR ventricles showed sigificantly less $Na^{+}$,$K^{+}$-ATPase activity and number of phosphorylation sites when compared to snrcolemma 1mm the WKY ventricles. Equilibrium binding of [$^3H$〕ouabain and the turnovcr number of myocardial $Na^{+}$,$K^{+}$-ATPast however, wee the same for both groups. These results. indicate that the low affinity(${\alpha}$, or ${\alpha}_1$) isoform for ouabain is reduced in SHR compared to WKY but that the high affinity(${\alpha}$+, or ${\alpha}_2$) isoform is the same in ventricles of SHR and WKY. The reduced amount of at isoform of the $Na^{+}$,$K^{+}$-ATPasc in prehypertensive SHR ventricles may play some pole in the development of hypertension.

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The Effects of Intracellular Monocarboxylates on the ATP-sensitive Potassium Channels in Rabbit Ventricular Myocytes

  • Kim, Na-Ri;Han, Jin;Kim, Eui-Yong;Ho, Won-Kyung;Earm, Yung E.
    • The Korean Journal of Physiology and Pharmacology
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    • 제2권5호
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    • pp.581-589
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    • 1998
  • A regulating mechanism of the ATP-sensitive potassium channels $(K_{ATP}\;channels)$ is yet to fully explained. This study was carried out to investigate the effects of intracellular application of monocarboxylates (acetate, formate, lactate, and pyruvate) on $K_{ATP}$ channels in isolated rabbit ventricular myocytes. Single channel currents of $K_{ATP}$ channels were recorded using the excised inside-out or permeabilized attached (open-cell) patch-clamp technique at room temperature. Intracellular application of acetate, formate and pyruvate led to an inhibition of channel activity, whereas intracellular application of lactate increased channel activity. These effects were reversible upon washout. Analysis of single channel kinetics showed that monocarboxylates did not affect open-time constant and close-time constant. These results suggest that monocarboxylates participate in modulating $K_{ATP}$ channels activity in cardiac cells and that modulation of $K_{ATP}$ channels activity may resolve the discrepancy between the low $K_i$ in excised membrane patches and high levels of intracellular ATP concentration during myocardial ischemia or hypoxia.

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Role of Stretch-Activated Channels in Stretch-Induced Changes of Electrical Activity in Rat Atrial Myocytes

  • Youm, Jae-Boum;Jo, Su-Hyun;Leem, Chae-Hun;Ho, Won-Kyung;Earm, Yung E.
    • The Korean Journal of Physiology and Pharmacology
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    • 제8권1호
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    • pp.33-41
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    • 2004
  • We developed a cardiac cell model to explain the phenomenon of mechano-electric feedback (MEF), based on the experimental data with rat atrial myocytes. It incorporated the activity of ion channels, pumps, exchangers, and changes of intracellular ion concentration. Changes in membrane excitability and $Ca^{2+}$ transients could then be calculated. In the model, the major ion channels responsible for the stretch-induced changes in electrical activity were the stretch-activated channels (SACs). The relationship between the extent of stretch and activation of SACs was formulated based on the experimental findings. Then, the effects of mechanical stretch on the electrical activity were reproduced. The shape of the action potential (AP) was significantly changed by stretch in the model simulation. The duration was decreased at initial fast phase of repolarization (AP duration at 20% repolarization level from 3.7 to 2.5 ms) and increased at late slow phase of repolarization (AP duration at 90% repolarization level from 62 to 178 ms). The resting potential was depolarized from -75 to -61 mV. This mathematical model of SACs may quantitatively predict changes in cardiomyocytes by mechanical stretch.

마스크 착용 여부에 따른 가슴압박 질, 주관적 피로도, 근활성도 비교 (Comparison of chest compression quality, subjective fatigue, and muscle activity according to wearing a mask)

  • 김예림;박재성
    • 한국응급구조학회지
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    • 제26권2호
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    • pp.61-71
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    • 2022
  • Purpose: This experimental study compared the chest compression quality, muscle activity, and subjective fatigue of paramedic students who did or did not wear a mask. Methods: The subjects of this study were 13 paramedic students at college D located in B city. Frequency percentages, mean standard deviations, and paired sample t-tests were conducted using the SPSS/WIN 23.0 program. Results: This study revealed that chest compression depths (t=-2.151, p=.053) and compression rates (t=-2.714, p=.019) were higher in mask-wearers, while muscle activity and subjective fatigue (t=2.382, p=.035) of the erector spinae (t=7.082, p=.001), rectus abdominis (t=4.776, p=.001), and pectoralis major muscles (t=3.193, p=.008) were lower in mask-wearers. Conclusion: The results of this study can be used as a basis to increase the resuscitation rates of cardiac arrest patients and provision of high-quality chest compressors to rescuers when infectious diseases recur in the future.

수념산(手拈散)이 허혈성(虛血性) 심장(心臟)의 심근(心筋) 효소(酵素)에 미치는 영향(影響) (An Experimental Study on the Effect of Soojeomsan(Shou Nian San) on CPK and Na-K ATPase of Ischemic and Perfused Rat Heart)

  • 강관호;문상관;조기호;김영석;배형섭;이경섭
    • 대한한방내과학회지
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    • 제18권2호
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    • pp.220-228
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    • 1997
  • Background The stenosis of the coronary artery may decrease myocardial oxygen supply and occur myocardial ischemia or infarction. Soojeomsan, one of analgesics is generally regarded to have the effect of vitalizing blood, expelling blood stasis and alleviation cardiac pain. Methods The purpose of this experimental study is to find the influence of Soojeomsan on cardiac enzyme (CPK, Na-K ATPase) of ischemic and reperfused rat hearts which are isolated under the Langendorff apparatus. Ischemia was induced In isolated hearts of Sprague-Dawley rats by ceasing the perfusion for 20 minutes. The experiments were divided into a normal saline orally administered group(control group), a Soojeomsan orally 20ml administered group(sample A) and a Soojeomsan orally 30ml administered group(sample B). The CPK (creatinine phosphokinase) and Na-K ATPase activity of this three group were measured and compared in order to assess the influence of Soojeomsan on protection of isolated rat hearts from ischemia. Results 1. CPK was significantly reduced in Sample A group and Sample B group in comparison with control group in reperfusion(P<0.01), and there were no significant difference between Sample A and B. 2. Na-K ATPase activity was significantly increased in Sample A group and Sample B group in comparison with control group in ischemia(P<0.001), and the activity was significantly higher in Sample B then in Sample A.(P<0.01) 3. There were no significant difference in Na-K ATPase activity of the three groups after reperfusion. Conclusion Soojeomsan has effects to decrease CPK activity and activate Na pump. This result in protection of the myocardium of isolated rat hearts from ischemia.

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