Protective effect and mechanism of K_(ATp) channel opener on the sinoatrial node cells of neonatal rat cultured in simulated ischemia-reperfusion  

作　　者：宋治远 仝识非 钟理 

机构地区：[1]Department of Cardiology, Southwest Hospital, Third Military Medical University, Chongqing 400038, China [2]Department of Cardiology, Southwest Hospital, Third Military Medical University, Chongqing 400038, Chinabjective: To study the effect of KATp channel opener and its possible mechanism on the sinoatrial node cells of neonatal rats which were cultured under simulated ischemia-reperfusion. Methods: Freshly isolated sinoatrial node (SAN) cells of neonatal rats were purified and cultured for 2 d, and then they were randomly divided into the control, simulated ischemia-reperfusion group (I/R group) , group intervened with KATp channel opener pinacidil (P + I/R group), KATP Channel blocking agent 5-HD (5-HD + I/R group) , and group with the 2 agents at same time (5-HD + P + I/R group) . The survival rate of cells was measured by flow cytometry and the content of intracellular calcium in the cells of each group was detected with laser confocal microscopy. Results: ①The survival rate of SAN cells in I/R group [ (51. 79±6. 28)% ] was remarkably significantly lower than in control [ (95. 08±10. 48)% ] (P < 0.001), and very significantly lower than in P + I/R group [ (63. 77±5. 35) % ] (P<0.01), however, those of 5-HD + P + I/R group [(52. 88±6. 25)% ] and 5-HD+I/R group [ (53. 16±5. 35)% ] was significantly lower compared with that in P + I/R group (P <0. 01) [3]②When the average fluorescence intensity of sinoatrial node cells in the control was regarded as 100% , the relative fluorescence intensities of each group were: ( 374±52) % in I/R group, significantly higher than that of control (P <0. 01) [4]( 162±20)% in P + I/R group, declining significantly than that of I/R group (P<0.01) [5](385?6)% in 5-HD+ P + I/R group and (379±44)% in 5-HD + I/R group, increasing significantly than that of I/R group (P<0.01). Conclusion: ①Simulated ischemia-reperfusion can significantly reduce the survival rate of SAN cells, and can also lead to the overload of intracellular calcium in them.②KATp channel opener, pi

出　　处：《Journal of Medical Colleges of PLA(China)》2003年第4期205-208,共4页中国人民解放军军医大学学报（英文版）

基　　金：Supported by National Natural Science Foundation of China (No. 30070314)

摘　　要：Objective: To study the effect of KATp channel opener and its possible mechanism on the sinoatrial node cells of neonatal rats which were cultured under simulated ischemia-reperfusion. Methods: Freshly isolated sinoatrial node (SAN) cells of neonatal rats were purified and cultured for 2 d, and then they were randomly divided into the control, simulated ischemia-reperfusion group (I/R group) , group intervened with KATp channel opener pinacidil (P + I/R group), KATP Channel blocking agent 5-HD (5-HD + I/R group) , and group with the 2 agents at same time (5-HD + P + I/R group) . The survival rate of cells was measured by flow cytometry and the content of intracellular calcium in the cells of each group was detected with laser confocal microscopy. Results: ① The survival rate of SAN cells in I/R group [ (51. 79±6. 28)% ] was remarkably significantly lower than in control [ (95. 08±10. 48)% ] (P < 0.001), and very significantly lower than in P + I/R group [ (63. 77±5. 35) % ] (P<0.01), however, those of 5-HD + P + I/R group [(52. 88±6. 25)% ] and 5-HD+I/R group [ (53. 16±5. 35)% ] was significantly lower compared with that in P + I/R group (P <0. 01) ; ② When the average fluorescence intensity of sinoatrial node cells in the control was regarded as 100% , the relative fluorescence intensities of each group were: ( 374±52) % in I/R group, significantly higher than that of control (P <0. 01) ; ( 162±20)% in P + I/R group, declining significantly than that of I/R group (P<0.01); (385?6)% in 5-HD+ P + I/R group and (379±44)% in 5-HD + I/R group, increasing significantly than that of I/R group (P<0.01). Conclusion: ① Simulated ischemia-reperfusion can significantly reduce the survival rate of SAN cells, and can also lead to the overload of intracellular calcium in them.② KATp channel opener, pinacidil, exerts protective effect on the cells under simulated ischemia-reperfusion, which may be associated with the decrease of intracellular calcium loading in them.Objective: To study the effect of KATP channel opener and its possible mechanism on the sinoatrial node cells of neonatal rats which were cultured under simulated ischemia-reperfusion. Methods: Freshly isolated sinoatrial node (SAN) cells of neonatal rats were purified and cultured for 2 d, and then they were randomly divided into the control, simulated ischemia-reperfusion group (I/R group), group intervened with KATP channel opener pinacidil (P+I/R group), KATP Channel blocking agent 5-HD (5-HD+I/R group), and group with the 2 agents at same time (5-HD+P+I/R group). The survival rate of cells was measured by flow cytometry and the content of intracellular calcium in the cells of each group was detected with laser confocal microscopy. Results: ① The survival rate of SAN cells in I/R group [(51.79±6.28)%] was remarkably significantly lower than in control [(95.08±10.48)%] (P<0.001), and very significantly lower than in P+I/R group [(63.77±5.35)%] (P<0.01), however, those of 5-HD+P+I/R group [(52.88±6.25)%] and 5-HD+I/R group [(53.16±5.35)%] was significantly lower compared with that in P+I/R group (P<0.01); ② When the average fluorescence intensity of sinoatrial node cells in the control was regarded as 100%, the relative fluorescence intensities of each group were: (374±52)% in I/R group, significantly higher than that of control (P<0.01); (162±20)% in P+I/R group, declining significantly than that of I/R group (P<0.01); (385±56)% in 5-HD+P+I/R group and (379±44)% in 5-HD+I/R group, increasing significantly than that of I/R group (P<0.01). Conclusion: ① Simulated ischemia-reperfusion can significantly reduce the survival rate of SAN cells, and can also lead to the overload of intracellular calcium in them. ② KATP channel opener, pinacidil, exerts protective effect on the cells under simulated ischemia-reperfusion, which may be associated with the decrease of intracellular calcium loading in them.

关 键 词：sinoatrial node  ischemia-reperfusion  KATP channel opener intracellular calcium 

分 类 号：R541.7[医药卫生—心血管疾病]