硫化氢对异丙肾上腺素所致早后除极和触发活动的影响

Effects of H2S on Early Afterdepolarization and Triggered Activity Induced by Isoprenaline in Guinea Pig Papillary Muscles

目的探索硫化氢对异丙肾上腺素所致豚鼠乳头肌早后除极及触发活动的影响。方法应用细胞内玻璃微电极技术记录豚鼠乳头肌动作电位,用异丙肾上腺素诱发早后除极和触发活动,观察硫化氢对早后除极和触发活动的影响。结果 1)含异丙肾上腺素(50 nmol/L)的K-H液灌流可引起豚鼠右心室乳头肌产生早后除极并出现触发活动,有时触发活动会出现持久的节律性活动。2)NaHS(100、200μmol/L)预处理可显著降低异丙肾上腺素诱发的早后除极波幅及发生率和触发活动的发生率(**P<0.01),NaHS 200μmol/L还明显延长早后除极的潜伏期(*P<0.05)。结论硫化氢抑制异丙肾上腺素所致早后除极及触发活动的发生。

Objective To investigate the effects of H2S on early afterdepolarization and triggered activity（TA） induced by iso- prenaline in guinea pig papillary muscles. Methods The action potentials of guinea pig papillary muscles were recorded with a glass microelectrode, and the effects of H2S on EAD and TA induced by Iso were also observed. Results With K-H solution containing Iso superfusing guinea pig papillary muscles, the EAD and TA can be induced with durable rhythmic activities of TA sometimes. After pretreatment with NaHS（100, 200 mol/L）, the EAD amplitude and occurrence rates of EAD and TA can be decreased significantly （＊＊P 〈 0.01 ）. NariS solution（20l） mol/L） also can prolong the incubation period of EAD. Conclusion H2S can inhibite EAD and TA induced by Iso（＊P 〈 0.0,5）.