Objective Allocryptopine （ALL） is an effective alkaloid of Corydalis decumbens （Thunb.） Pers. Papaveraceae and has proved to be an- ti-arrhythmic. The purpose of our study is to investigate the effects of ALL on t...Objective Allocryptopine （ALL） is an effective alkaloid of Corydalis decumbens （Thunb.） Pers. Papaveraceae and has proved to be an- ti-arrhythmic. The purpose of our study is to investigate the effects of ALL on transmural repolarizing ionic ingredients of outward potassium current （Ito） and slow delayed rectifier potassium current （IKs）. Methods The monophasic action potential （MAP） technique was used to record the MAP duration of the epicardium （Epi）, myocardium （M） and endocardium （Endo） of the rabbit heart and the whole cell patch clamp was used to record/to and IKs in cardiomyocytes of Epi, M and Endo layers that were isolated from rabbit ventricles. Results The effects of ALL on MAP of Epi, M and Endo layers were disequilibrium. ALL could effectively reduce the transmural dispersion of repolarization （TDR） in rabbit transmural ventricular wall. ALL decreased the current densities of/to and IKs in a voltage and concentration dependent way and narrowed the repolarizing differences among three layers. The analysis of gating kinetics showed ALL accelerated the channel activation ofIto in M layers and partly inhibit the channel openings of/to in Epi, M and Endo cells. On the other hand, ALL mainly slowed channel deactivation of IKs channel in Epi and Endo layers without affecting its activation. Conclusions Our study gives partially explanation about the mechanisms of tmnsmural inhibition of/to and IKs channels by ALL in rabbit myocardium. These findings provide novel perspective regarding the anti-arrhythmogenesis application of ALL in clinical settings.展开更多
Objective To explore the effect of allocryptopine （All） on the Late sodium current （INa,Late） of atrial myocytes in spontaneously hyper- tensive rats （SHR）. Method The enzyme digestion method was used to separat...Objective To explore the effect of allocryptopine （All） on the Late sodium current （INa,Late） of atrial myocytes in spontaneously hyper- tensive rats （SHR）. Method The enzyme digestion method was used to separate single atrial myocytes from SHR and Wistar-Kyoto rat （WKY） rats. INa,Late was record by patch-clamp technique and the effect of All on the current was evaluated. Results Comparing with WKY cells, markedly increasing of INa,Late current in SHR myocytes was found from 0.24 ± 0.02 pA/pF of WKY cells to 1.73± 0.04 pA/pF of SHR cells （P 〈 0.01, n = 15）. After treament with 30 μmol/L All; the current densities was reduced to 0.92 ± 0.03 pA/pF. The ratio of INa,Late/INa,peak of WKY and SHR were 0.09% ± 0.01% and 0.71% ± 0.02%, INa, Late/INa,peak of SHR was reduced to 0.37% ± 0.02% by 30 μmol/L All （P 〈 0.01, n = 15）. We also determined the effect of All on the gating mechanism of the INa,Late in the SHR cells. It was found that All decreased the INa,Late by alleviating the inactivation of the channels and increasing the window current of sodium channel. Conclusion Increased INa,Late in SHR atrial myocytes and the prolonged APD were inhibited by All coming from Chinese herb medicine.展开更多
文摘Objective Allocryptopine （ALL） is an effective alkaloid of Corydalis decumbens （Thunb.） Pers. Papaveraceae and has proved to be an- ti-arrhythmic. The purpose of our study is to investigate the effects of ALL on transmural repolarizing ionic ingredients of outward potassium current （Ito） and slow delayed rectifier potassium current （IKs）. Methods The monophasic action potential （MAP） technique was used to record the MAP duration of the epicardium （Epi）, myocardium （M） and endocardium （Endo） of the rabbit heart and the whole cell patch clamp was used to record/to and IKs in cardiomyocytes of Epi, M and Endo layers that were isolated from rabbit ventricles. Results The effects of ALL on MAP of Epi, M and Endo layers were disequilibrium. ALL could effectively reduce the transmural dispersion of repolarization （TDR） in rabbit transmural ventricular wall. ALL decreased the current densities of/to and IKs in a voltage and concentration dependent way and narrowed the repolarizing differences among three layers. The analysis of gating kinetics showed ALL accelerated the channel activation ofIto in M layers and partly inhibit the channel openings of/to in Epi, M and Endo cells. On the other hand, ALL mainly slowed channel deactivation of IKs channel in Epi and Endo layers without affecting its activation. Conclusions Our study gives partially explanation about the mechanisms of tmnsmural inhibition of/to and IKs channels by ALL in rabbit myocardium. These findings provide novel perspective regarding the anti-arrhythmogenesis application of ALL in clinical settings.
基金This work was supported by the grant from the National Natural Science Foundation of China （grant number. No： 81030002,81170177, 81100215, 81373835）.
文摘Objective To explore the effect of allocryptopine （All） on the Late sodium current （INa,Late） of atrial myocytes in spontaneously hyper- tensive rats （SHR）. Method The enzyme digestion method was used to separate single atrial myocytes from SHR and Wistar-Kyoto rat （WKY） rats. INa,Late was record by patch-clamp technique and the effect of All on the current was evaluated. Results Comparing with WKY cells, markedly increasing of INa,Late current in SHR myocytes was found from 0.24 ± 0.02 pA/pF of WKY cells to 1.73± 0.04 pA/pF of SHR cells （P 〈 0.01, n = 15）. After treament with 30 μmol/L All; the current densities was reduced to 0.92 ± 0.03 pA/pF. The ratio of INa,Late/INa,peak of WKY and SHR were 0.09% ± 0.01% and 0.71% ± 0.02%, INa, Late/INa,peak of SHR was reduced to 0.37% ± 0.02% by 30 μmol/L All （P 〈 0.01, n = 15）. We also determined the effect of All on the gating mechanism of the INa,Late in the SHR cells. It was found that All decreased the INa,Late by alleviating the inactivation of the channels and increasing the window current of sodium channel. Conclusion Increased INa,Late in SHR atrial myocytes and the prolonged APD were inhibited by All coming from Chinese herb medicine.
