钙调神经磷酸酶对肥大乳鼠心室肌细胞L型钙离子通道电流的调控作用

目的 探讨钙调神经磷酸酶(CaN)对乳鼠肥大心室肌细胞L型钙离子通道电流(ICa-L)的调控作用.方法 1d龄SD大鼠乳鼠心室肌细胞,培养24 h后换无血清培养基,分组干预48 h:Null组为空腺病毒载体干预,Null+PE组为空腺病毒载体联合苯肾上腺素(PE)干预,Ad-CnAβshRNA(A1)组给予重组腺病毒shRNA干扰载体介导沉默编码CaN之A亚基β亚型(CnAβ)基因干预,最后为A1+PE组.免疫印迹检测CnAβ蛋白表达;全细胞膜片钳技术记录ICa-L离子通道电流.结果 PE刺激使心室肌细胞肥大、CnAβ蛋白表达上调、Ica-I.离子通道电流密度增加.而沉默CnAβ基因能明显抑制PE刺激的上述效应.结论 CaN参与了肥大乳鼠心室肌细胞kL的调控.

Regulation of Calcineurin signal on L type calcium ion channel current of hypertrophic ventricular myocytes from neonatal rats

Objective To study the effects of Calcineurin on L type calcium ion channel current (ICa L) regulation of hypertrophic ventricular myocytes from neonatal rat.Methods The ventricular myocytes of 1 day-old SpragueDawley rats were isolated and cultured for 24 h,and they were divided into four groups according to the treatment administered then cultured for 48 h:Null group,Null+ phenylephrine (PE) group,Ad-CnAβshRNA (A1) group and A1+PE group.The protein expression of Calcineurin A subunit β (CnAβ) was assayed by western blot test.Whole cell patch clamp technique was used to record ICa-L channel current.Results PE stimulation significant induced cell hypertrophy,up-regulated the protein expression of CnAβ and increased the ICa-L channel current density.Ad-CnAβshRNA intervention inhibited the effects of PE stimulation.Conclusion Calcineurin is involved in the regulation of ICa-L in neonatal hypertrophy ventricular myocytes.