标本来源: 小鼠,左心房,右心房,左心室, Langendorff灌流
Mapping实验可标测心房、心室组织传导速度
此案例中,科研工作者发现了MKK4基因敲除小鼠心脏Cx43减少,在投稿Circulation后被要求补做mapping实验,从电生理功能上证明Cx43减少影响了左室的动作电位传导速度并因此构成了心律失常的形成基础。如图A,64通道电极放置于小鼠左室,中间电极点给电刺激,可看出基因敲除鼠的AP传导速度明显慢。心室肌传导速度和心肌走向相关,因此文中分析了横向纵向两种传导速度(图B)。
关于心室的mapping实验完成后,作者又标测了左右心房,发现老年基因敲除鼠的心房电传导异常(图C,D),又发表了第二篇论文。
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Cartwright EJ, Wang X. Mitogen-activated protein kinase kinase 4 deficiency in cardiomyocytes causes connexin 43 reduction and couples hypertrophy
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