Background Shensong Yangxin （SSYX） is one of the compound recipe of Chinese materia medica. This study was conducted to investigate the effects of SSYX on sodium current （/Na）, L-type calcium current （/Ca.L）, tr...Background Shensong Yangxin （SSYX） is one of the compound recipe of Chinese materia medica. This study was conducted to investigate the effects of SSYX on sodium current （/Na）, L-type calcium current （/Ca.L）, transient outward potassium current （/to）, delayed rectifier current （/K）, and inward rectifier potassium currents （/K1） in isolated ventricular myocytes. Methods Whole cell patch-clamp technique was used to study ion channel currents in enzymatically isolated guinea pig or rat ventricular myocytes. Results SSYX decreased peak Na by （44.84±7.65）% from 27.21±5.35 to 14.88±2..75 pA/pF （n=-5, P〈0.05）. The medicine significantly inhibited the /Ca,L. At concentrations of 0.25, 0.50, and 1.00 g/100 ml, the peak/Ca,L was reduced by （19.22±1.10）%, （44.82±6.50）% and （50.69±5.64）%, respectively （n=5, all P〈0.05）. SSYX lifted the I-V curve of both /Na and /Ca,L without changing the threshold, peak and reversal potentials. At the concentration of 0.5%, the drug blocked the transient component of /to by 50.60% at membrane voltage of 60 mV and negatively shifted the inactive curve and delayed the recovery from channel inactivation. The tail current density of /K was decreased by （30.77±1.11）% （n=5, P〈0.05） at membrane voltage of 50 mV after exposure to the medicine and the time-dependent activity of /K was also inhibited. Similar to the effect on /K, the SSYX inhibited /K1 by 33.10% at the test potential of -100 mV with little effect on reversal potential and the rectification property. Conclusions The experiments revealed that SSYX could block multiple ion channels such as /Na /Ca,L, /k, /to and /K1, which may change the action potential duration and contribute to some of its antiarrhythmic effects.展开更多
Background Because of the potential proarrhythmic effect of current antiarrhythmic drugs, it is still desirable to find safer antiarrhythmic drugs worldwide. Paeoniflorin is one of the Chinese herb monomers that have ...Background Because of the potential proarrhythmic effect of current antiarrhythmic drugs, it is still desirable to find safer antiarrhythmic drugs worldwide. Paeoniflorin is one of the Chinese herb monomers that have different effects on many ion channels. The present study aimed to determine the effects of paeoniflorin on cardiac ion channels.Methods Whole-cell patch-clamp technique was used to record ion channel currents. L-type calcium current （/Ca-L）,inward rectifier potassium current （/K1）, and transient outward potassium current （/to1） were studied in rat ventricular myocytes and sodium current （/Na）, slow delayed rectifier current （/Ks）, and HERG current （/Kr） were investigated in transfected human embryonic kidney 293 cells.Results One hundred μmol/L paeoniflorin reduced the peak /ca-L by 40.29% at the test potential of ±10 mV （from （-9.78±0.52） pA/pF to （-5.84±0.89） pA/pF, n=5, P=0.028）. The steady-state activation curve was shifted to more positive potential in the presence of the drug. The half activation potentials were （-11.22±0.27） mV vs. （-5.95±0.84） mV （n=5,P=0.007）, respectively. However, the steady-state inactivation and the time course of recovery from inactivation were not changed. One hundred μmol/L paeoniflorin completely inhibited the peak /Na and the effect was reversible. Moreover,paeoniflorin inhibited the /K1 by 30.13% at the test potential of -100 mV （from （-25.26±8.21） pA/pF to （-17.65±6.52）pA/pF, n=6, F=0.015） without effects on the reversal potential and the rectification property. By contrast, 100 μmol/L paeoniflorin had no effects on/to1, /Ks or /Kr channels.Conclusions The study demonstrated that paeoniflorin blocked /Ca-L, /Na, and /Kf without affecting /to1, /Ks, or /Kr. The multi-channel block effect may account for its antiarrhythmic effects with less proarrhythmic potential.展开更多
In Traditional Chinese Medicine,stimulation of the Neiguan spot has been utilized to treat palpitations and symptoms related to different cardiovascular diseases.We evaluated whether acupuncture might exert an antiarr...In Traditional Chinese Medicine,stimulation of the Neiguan spot has been utilized to treat palpitations and symptoms related to different cardiovascular diseases.We evaluated whether acupuncture might exert an antiarrhythmic effect on patients with paroxysmal or persistent atrial fibrillation(AF).Two sets of data are reviewed.The first included patients with persistent AF who underwent electrical cardioversion to restore sinus rhythm.The second included patients with symptomatic paroxysmal AF.All subjects had normal ventricular function.Acupuncture treatment consisted of 10 acupuncture sessions on a once a week basis with puncturing of the Neiguan,Shenmen and Xinshu spots.In patients with persistent AF,the recurrence rate after acupuncture treatment was similar to that observed in patients on amiodarone,but significantly smaller than that measured after sham acupuncture treatment or in the absence of any antiarrhythmic drugs.In a small group of patients with paroxysmal AF,acupuncture resulted in a significant reduction in the number and duration of symptomatic AF episodes.In conclusion,we observed that acupuncture of the Neiguan spot was associated with an antiarrhythmic effect,which was evident in patients with both persistent and paroxysmal AF.These preliminary data,observed in 2 small groups of AF patients,need to be validated in a larger population but strongly suggest that acupuncture may be an effective non-invasive and safe antiarrhythmic tool in the management of these patients.展开更多
文摘Background Shensong Yangxin （SSYX） is one of the compound recipe of Chinese materia medica. This study was conducted to investigate the effects of SSYX on sodium current （/Na）, L-type calcium current （/Ca.L）, transient outward potassium current （/to）, delayed rectifier current （/K）, and inward rectifier potassium currents （/K1） in isolated ventricular myocytes. Methods Whole cell patch-clamp technique was used to study ion channel currents in enzymatically isolated guinea pig or rat ventricular myocytes. Results SSYX decreased peak Na by （44.84±7.65）% from 27.21±5.35 to 14.88±2..75 pA/pF （n=-5, P〈0.05）. The medicine significantly inhibited the /Ca,L. At concentrations of 0.25, 0.50, and 1.00 g/100 ml, the peak/Ca,L was reduced by （19.22±1.10）%, （44.82±6.50）% and （50.69±5.64）%, respectively （n=5, all P〈0.05）. SSYX lifted the I-V curve of both /Na and /Ca,L without changing the threshold, peak and reversal potentials. At the concentration of 0.5%, the drug blocked the transient component of /to by 50.60% at membrane voltage of 60 mV and negatively shifted the inactive curve and delayed the recovery from channel inactivation. The tail current density of /K was decreased by （30.77±1.11）% （n=5, P〈0.05） at membrane voltage of 50 mV after exposure to the medicine and the time-dependent activity of /K was also inhibited. Similar to the effect on /K, the SSYX inhibited /K1 by 33.10% at the test potential of -100 mV with little effect on reversal potential and the rectification property. Conclusions The experiments revealed that SSYX could block multiple ion channels such as /Na /Ca,L, /k, /to and /K1, which may change the action potential duration and contribute to some of its antiarrhythmic effects.
文摘Background Because of the potential proarrhythmic effect of current antiarrhythmic drugs, it is still desirable to find safer antiarrhythmic drugs worldwide. Paeoniflorin is one of the Chinese herb monomers that have different effects on many ion channels. The present study aimed to determine the effects of paeoniflorin on cardiac ion channels.Methods Whole-cell patch-clamp technique was used to record ion channel currents. L-type calcium current （/Ca-L）,inward rectifier potassium current （/K1）, and transient outward potassium current （/to1） were studied in rat ventricular myocytes and sodium current （/Na）, slow delayed rectifier current （/Ks）, and HERG current （/Kr） were investigated in transfected human embryonic kidney 293 cells.Results One hundred μmol/L paeoniflorin reduced the peak /ca-L by 40.29% at the test potential of ±10 mV （from （-9.78±0.52） pA/pF to （-5.84±0.89） pA/pF, n=5, P=0.028）. The steady-state activation curve was shifted to more positive potential in the presence of the drug. The half activation potentials were （-11.22±0.27） mV vs. （-5.95±0.84） mV （n=5,P=0.007）, respectively. However, the steady-state inactivation and the time course of recovery from inactivation were not changed. One hundred μmol/L paeoniflorin completely inhibited the peak /Na and the effect was reversible. Moreover,paeoniflorin inhibited the /K1 by 30.13% at the test potential of -100 mV （from （-25.26±8.21） pA/pF to （-17.65±6.52）pA/pF, n=6, F=0.015） without effects on the reversal potential and the rectification property. By contrast, 100 μmol/L paeoniflorin had no effects on/to1, /Ks or /Kr channels.Conclusions The study demonstrated that paeoniflorin blocked /Ca-L, /Na, and /Kf without affecting /to1, /Ks, or /Kr. The multi-channel block effect may account for its antiarrhythmic effects with less proarrhythmic potential.
文摘In Traditional Chinese Medicine,stimulation of the Neiguan spot has been utilized to treat palpitations and symptoms related to different cardiovascular diseases.We evaluated whether acupuncture might exert an antiarrhythmic effect on patients with paroxysmal or persistent atrial fibrillation(AF).Two sets of data are reviewed.The first included patients with persistent AF who underwent electrical cardioversion to restore sinus rhythm.The second included patients with symptomatic paroxysmal AF.All subjects had normal ventricular function.Acupuncture treatment consisted of 10 acupuncture sessions on a once a week basis with puncturing of the Neiguan,Shenmen and Xinshu spots.In patients with persistent AF,the recurrence rate after acupuncture treatment was similar to that observed in patients on amiodarone,but significantly smaller than that measured after sham acupuncture treatment or in the absence of any antiarrhythmic drugs.In a small group of patients with paroxysmal AF,acupuncture resulted in a significant reduction in the number and duration of symptomatic AF episodes.In conclusion,we observed that acupuncture of the Neiguan spot was associated with an antiarrhythmic effect,which was evident in patients with both persistent and paroxysmal AF.These preliminary data,observed in 2 small groups of AF patients,need to be validated in a larger population but strongly suggest that acupuncture may be an effective non-invasive and safe antiarrhythmic tool in the management of these patients.
