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Effects of 2-[p-(Dimethylamino)Styrl] PyridineMethiodide on Slow Response Action Potentialand Slow lnward Current of Guinea PigPapillary Muscles
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作者 毛新民 李迪民 +2 位作者 周承明 王晓雯 张克锦 《Journal of Chinese Pharmaceutical Sciences》 CAS 1995年第1期12-16,共5页
The effects of 2-[p-(Dimethylamino)styryl] pyridine methiodide(DSPM)on slow response action potential(SRAP)and slow inward current(Isi) of guinea pig papillary muscles were studied by intracellular microelectrodes and... The effects of 2-[p-(Dimethylamino)styryl] pyridine methiodide(DSPM)on slow response action potential(SRAP)and slow inward current(Isi) of guinea pig papillary muscles were studied by intracellular microelectrodes and voltage clamp techniques.The APA and V_(max) of SRAP induced by high K ̄+were decreased after 50 min of perfusion with DSPM solu- tion. Isi was suppressed from a peak value of8.8± 1.6μA to 5.7± 1.8μA, The results indicated that DSPM has a selective blocking effect on calcium channel. 展开更多
关键词 p-(Dimethylamino)styryl] pyridine methiodide(DSPM) Verapamil Calcium chloride papillary muscle Calcium channel Voltage clamp Action potential
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Effects of hexametazidine on physiological properties of guinea-pig papillary muscles
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作者 贾铀生 赵德化 盛宝恒 《Journal of Medical Colleges of PLA(China)》 CAS 1991年第2期170-172,共3页
Effects of hexametazidine [1,4-di(2,3,4-trimethoxybenzyl)piperazine] on the physiological properties of guinea-pig papillary muscles were investigated. Hexametazidine possesses a concentration-dependent negative inotr... Effects of hexametazidine [1,4-di(2,3,4-trimethoxybenzyl)piperazine] on the physiological properties of guinea-pig papillary muscles were investigated. Hexametazidine possesses a concentration-dependent negative inotropic effect (IC_(50)=81.8±16.9μmol/L).The effect of hexametazidine(30.8μmol/L)was antago- nized completely by increasing the concentration of Ca^(2+)from 1.8 to 5.4mmol/L. Hexametazidine(30.8μmol/L)increased the threshold concentration of adrenaline for inducing the automaticity of the muscles from 3.95±1.80 to 6.67±4.84μmol/L (P<0.05).It prolonged the functional refractory period from 218±14 to 254±20ms (P<0.05)at the concentration of 61.6μmol/L.Hexametazidine(6.2μmol/L)antago- nized the positive inotropic effect of isoprenaline competitively and of histamine non-competitively(pA 2 and pD2′ values were 5.45 and 4.13, respectively). 展开更多
关键词 PIPERAZINE beta adrenergic receptors histamine H_2 receptors refractory period papillary muscles
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NEGATIVE EFFECTS OF ETHANOL ON ISOLATED GUINEA PIG LEFT ATRIUM AND PAPILLARY MUSCLES
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作者 胡浩 臧伟进 +4 位作者 于晓江 王昌利 张凤杰 孙强 张春虹 《Journal of Pharmaceutical Analysis》 CAS 2002年第1期20-22,25,共4页
Objective To investigate the effects of ethanol on physiological characteristics of the isolated guinea pig left atrium and papillary muscles.Methods The effects of ethanol on contractility, post-rest potentiation a... Objective To investigate the effects of ethanol on physiological characteristics of the isolated guinea pig left atrium and papillary muscles.Methods The effects of ethanol on contractility, post-rest potentiation and positive staircase phenomenon were observed in isolated left atrium and papillary muscles of guinea pig.Results Ethanol(50.0,100.0,200.0mmol·L -1)prominently inhibited the contraction of papillary muscles. Ethanol(12.5,25.0,50.0,100.0,200.0mmol·L -1) inhibited the contraction of left atrium, and markedly decreased the post-rest potentiation of myocardial contractility in left atrium. High concentration of ethanol(100,200mmol·L -1) depressed the positive staircase phenomenon of isolated guinea pig left atrium.Conclusion These results suggest that ethanol induces inhibitory effects of the contractility, post-rest potentiation, positive staircase phenomenon of left atrium. The mechanism by which ethanol induces the negative inotropic effects may be related to decrease the amount of calcium released from the intracellular stores. 展开更多
关键词 ETHANOL left atrium papillary muscles CONTRACTILITY post-rest potentiation
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Lesson Eighty four Ventricular arrhythmias originating from papillary muscles in the right ventricle
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作者 童鸿 《心电与循环》 2018年第4期293-297,共5页
Patientcharacteristics Patients in this study consisted of eight consecutive patients with frequent premature ventricular complexes(PVCs) or both PVCs and ventricular tachycardia(VT)who had been referred for catheter ... Patientcharacteristics Patients in this study consisted of eight consecutive patients with frequent premature ventricular complexes(PVCs) or both PVCs and ventricular tachycardia(VT)who had been referred for catheter ablation and whose arrhythmia was mapped to one of the right ventricular(RV)papillary muscles(PAPs).The control group consisted of 10 consecutive patients who were referred for ablation of symptomatic idiopathic 展开更多
关键词 浦肯野电位 PVC VT 起搏标测 Lesson Eighty four Ventricular arrhythmias originating from papillary muscles in the right ventricle 乳头肌 室性心律失常
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EFFECTS OF DISMERINONE ON HIGH K~+ DEPOLARIZED SLOW RESPONSE ACTION POTENTIALS IN GUINEA PIG PAPILLARY MUSCLES
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作者 张殿增 李西宽 +1 位作者 赵更生 傅杰民 《Journal of Pharmaceutical Analysis》 CAS 1994年第1期47-51,共5页
The effects of dismerinone (DMR), a derivative of milrinone, on high K+ depolarized slow response action potentials (APs) and intracellular cAMP levels were studied in guinea pig papillary muscles. DMR induced slow AP... The effects of dismerinone (DMR), a derivative of milrinone, on high K+ depolarized slow response action potentials (APs) and intracellular cAMP levels were studied in guinea pig papillary muscles. DMR induced slow APs in high K+ depolorized guinea pig papillary muscles and increased APA, Vmaxand APD50 of the slow APs in dose dependent way ; cAMP levels in same preparations were elevated by DMR. These effects of DMR are similar to isoprenaline (ISO). Bead adrenocepter blocker propranolol had no influence on DMR effect. Overall, the results from this study suggested that effects of DMR were not related to Beta adrenocepter, and might be related to its inhibiting phosphodiesterase Ⅲ(PDE Ⅲ) action. 展开更多
关键词 dismerinone slow response action potentials cAMP guinea pig papillary muscles
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Delayed papillary muscle rupture after radiofrequency catheter ablation: A case report
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作者 Ze-Wei Sun Bi-Feng Wu +3 位作者 Xuan Ying Bi-Qi Zhang Lei Yao Liang-Rong Zheng 《World Journal of Clinical Cases》 SCIE 2021年第20期5556-5561,共6页
BACKGROUND With an increased number of surgical procedures involving the mitral annular region,the risk of mitral valve prolapse(MVP)has also increased.Previous studies have reported that worsening of MVP occurred ear... BACKGROUND With an increased number of surgical procedures involving the mitral annular region,the risk of mitral valve prolapse(MVP)has also increased.Previous studies have reported that worsening of MVP occurred early after radiofrequency catheter ablation(RFCA)at papillary muscles in ventricular tachycardia(VT)patients with preoperative MVP.CASE SUMMARY We report a case where MVP and papillary muscle rupture occurred 2 wk after RFCA in a papillary muscle originated VT patient without mitral valve regurgitation or prolapse before.The patient then underwent mitral valve replacement with no premature ventricular contraction or VT.During the surgery,a papillary muscle rupture was identified.Pathological examination showed necrosis of the papillary muscle.The patient recovered after mitral valve replacement.CONCLUSION Too many ablation procedures and energy should be avoided. 展开更多
关键词 Mitral valve prolapse Radiofrequency catheter ablation Ventricular tachycardia Mitral valve replacement DYSPNEA papillary muscles Case report
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Contractility detection of isolated mouse papillary muscle using myotronic Myostation-Intact device
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作者 Hong Lian Zhuyun Qin +5 位作者 Mengge Wu Peipei Zuo Lina Bai Minjie Lu Lulu Li Haitao Zhang 《Animal Models and Experimental Medicine》 CAS CSCD 2022年第5期445-452,共8页
Background:To understand the relationship between myocardial contractility and ex-ternal stimuli,detecting ex vivo myocardial contractility is necessary.Methods:We elaborated a method for contractility detection of is... Background:To understand the relationship between myocardial contractility and ex-ternal stimuli,detecting ex vivo myocardial contractility is necessary.Methods:We elaborated a method for contractility detection of isolated C57 mouse papillary muscle using Myostation-Intact system under different frequencies,volt-ages,and calcium concentrations.Results:The results indicated that the basal contractility of the papillary muscle was 0.27±0.03 mN at 10 V,500-ms pulse duration,and 1 Hz.From 0.1 to 1.0 Hz,con-tractility decreased with an increase in frequency(0.45±0.11-0.10±0.02 mN).The voltage-initiated muscle contractility varied from 3 to 6 V,and the contractility gradu-ally increased as the voltage increased from 6 to 10 V(0.14±0.02-0.28±0.03 mN).Moreover,the muscle contractility increased when the calcium concentration was increased from 1.5 to 3 mM(0.45±0.17-1.11±0.05 mN);however,the contractility stopped increasing even when the concentration was increased to 7.5 mM(1.02±0.23 mN).Conclusions:Our method guaranteed the survivability of papillary muscle ex vivo and provided instructions for Myostation-Intact users for isolated muscle contractility investigations. 展开更多
关键词 calcium concentration frequency isolated papillary muscle muscle contractility Myostation-intact VOLTAGE
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Papillary Muscle Relocation in Secondary Mitral Regurgitation: Midterm Outcomes
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作者 Pramote Porapakkham Pornwalee Porapakkham 《World Journal of Cardiovascular Diseases》 2022年第4期216-227,共12页
Background: Mitral valve repair in secondary mitral regurgitation is still uncertain as the chance of recurrence is approximately 30 percent after solely undersized annuloplasty. Some procedures adding to the sub... Background: Mitral valve repair in secondary mitral regurgitation is still uncertain as the chance of recurrence is approximately 30 percent after solely undersized annuloplasty. Some procedures adding to the subvalvular level are proposed to alleviate the recurrent rate. This study was to evaluate the clinical and echocardiographic outcomes of papillary muscle relocation plus undersized ring in secondary mitral regurgitation (2<sup>nd</sup> MR). Methods: Medical records of moderate to severe 2<sup>nd</sup> MR with tethering depth of more than 1 cm patients who underwent papillary muscle relocation plus undersized ring from 2014 to 2020 were reviewed. Clinical and echocardiographic parameters before and after operation were analyzed. Results: Thirty-two patients were included during the 6-year period. There was no perioperative mortality. Two patients died at one year from ischemic stroke and car accidents with overall 5-year survival of 93.7%. All patients were in NYHA class I and II with MR grading as trivial or mild at a median follow-up of 33 months. Postoperative mean tenting depth, area and posterior leaflet angle decreased remarkably from 1.18 cm, 2.61 cm<sup>2</sup> and 46.5 degree to 0.65 cm, 1.22 cm<sup>2</sup> and 28.6 degree, respectively (p 0.001, 0.02, and 0.01). Moreover, left ventricular function and remodeling were also notably improved (EF;38.2% vs 49.1%: p = 0.018, LVEDD;62.8 vs 54.6 mm: p = 0.005, LVESD;50.2 vs 42.4 mm: p = 0.01). Conclusions: Papillary muscle relocation combined with undersized annuloplasty improved mid-term clinical outcomes. Apart from reduction of recurrent MR rate, restoration of mitral configuration and reverse LV remodeling could be the effect of adding subvalvular correction in this pathology. 展开更多
关键词 papillary Muscle Relocation Secondary Mitral Regurgitation Left Ventricular REMODELING Tenting Depth Tenting Area Posterior Leaflet Angle
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THE INFLUENCE OF SAPONINS OF PANAX QUINQUEFOLIUM LEAF AND STEM ON THE SLOW ACTION POTENTIALS IN MYOCARDIUM
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作者 吴捷 孙晓东 +2 位作者 于晓江 刘东 刘传镐 《Journal of Pharmaceutical Analysis》 CAS 1995年第1期52-55,共4页
The effects of Saponins of Panax Quinquefolium Leaf and Stem(SPQLS)were evaluatedin the rabbit sinus node and in the guinea pig papillary muscles both showing slow responses in high[k+].and being exposed to 0.3 μmol/... The effects of Saponins of Panax Quinquefolium Leaf and Stem(SPQLS)were evaluatedin the rabbit sinus node and in the guinea pig papillary muscles both showing slow responses in high[k+].and being exposed to 0.3 μmol/L verapamil using conventional microelcctrode technique.Inthe sinus node, SPQLS 100 mg/L decreased the APA and Vmax.At the concentration of 200 mg/L,in addition to further depressing the upotroke,SPQIS decreased the SP4,shortened the APD and prolonged the SCL.In the guinea Pig papillary muscle,SPQLS shortened the APD and decreased theAPA as well as Vmax in high[k+3].When verapamil was exposed to the normal Tyrode's solution,SPQLS depressed the upstroke without-affecting the APD in the guinea pig papillary muscle.Thesefindings suggest that SPQLS exerted a blockade effect on the transmembrane Ca2+ influx and Na+ influx in myocardium. 展开更多
关键词 SPQLS sinus node papillary muscles action potentials VERAPAMIL
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Effects of Electric Stimulations Applied During Absolute Refractory Period on Ventricular Muscle from Rabbits 被引量:1
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作者 张海柱 崔长琮 +1 位作者 赵晓静 周忠 《South China Journal of Cardiology》 CAS 2002年第2期115-117,共3页
Objectives To investigate the influences of electric signals applied during absolute refractory period (ARP) on the contractility of isolated papillary muscle from rabbits. Methods Papillary muscle was exercised from ... Objectives To investigate the influences of electric signals applied during absolute refractory period (ARP) on the contractility of isolated papillary muscle from rabbits. Methods Papillary muscle was exercised from the right ventricle and was paced at 1 Hz. Biphasic square wave current pulse was delivered during the absolute refractory period (called CCM) in isolated, superfused, isometrically contractility rabbit papillary muscle. The peak tension (PT) of papillary muscle, as well as maximum positive tension change ( + dT/dtmax), were observed. Results Compared with the baseline, both PT and + dT/dtmax significantly increased during CCM stimulation by 18.2% and 21.4% respectively (P < 0. 05) . In addition, PT increased significantly with one or two beats following CCM signal application and reached a. new steady state level after a few beats. Once the CCM signals were turned off, the PT returned to the approximately baseline level ( P < 0. 05). Moreover, the effect of CCM on PT was dose - response to voltage. The obvious effect was at higher voltage. No effect was observed at lower voltage. Conclusions Electric signals delivered during the absolute refractory period can rapidly enhance the contractility of myocardium, which suggests that CCM signal is a novel potent method for contractility modulation. 展开更多
关键词 Contractility Absolute refractory period Electric signal papillary muscle Rabbit
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