摘要
目的 观察心肌细胞感染病毒后心肌细胞钙、钾通道电流及通道表达改变和牛磺酸的作用。方法 (1 )体外心肌细胞感染病毒 :用胰蛋白酶和胶原酶消化法分别获得大鼠、乳鼠培养和分离的心肌细胞并感染柯萨奇B3病毒 ,用于检测Ca2 +跨膜内流、电压依赖性钙通道电流 (ICa)和外向钾通道电流 (Iout)。 (2 )在体小鼠感染病毒 :BALB c小鼠腹腔内注射柯萨奇B3病毒 7d后取出心脏用于检测电压依赖性钙通道α1 亚单位抗原和电压调控性钾通道 (Kv)mRNA的表达。相应各组加入不同剂量的牛磺酸并观察其作用。结果 (1 )感染柯萨奇B3病毒后Ca2 +跨膜内流量及ICa增加 ,牛磺酸对其有抑制作用。 (2 )柯萨奇B3病毒感染使Iout明显增大 ,牛磺酸可使病毒感染后的Iout趋于恢复正常。(3)柯萨奇B3病毒感染后小鼠心肌出现强电压依赖性钙通道α1 亚基抗原阳性信号 ,Kv1 2、Kv2 1、Kv4 2mRNA与 3种探针的杂交信号亦明显增强 ,牛磺酸可使增强的阳性信号减弱。结论 柯萨奇B3病毒感染后心肌细胞钙、钾离子通道电流及表达均增加 。
Objective To investigate the effects of taurine on current of L type voltage dependent calcium channel (I Ca ), outward potassium current (I out ) and their expression in cardiomyocytes after coxsackievirus B3 (CVB3) infection Methods (1)Heart cell preparation and virus infection: monolayer culture heart cells were made from newborn SD rats hearts by 5 cycles of enzymatic digestion with trypsin solution and were used for detecting calcium influx across membrane (by liquid scintillating techniques and radioactive isotope 45 Ca 2+ ) Cardiomyocytes from the newborn SD rats were obtained using collagenase digestion and used for recording outward potassium current (I out ) (by Hamill patch clamp methods) Heart from adult SD rats was put to Langendoff installation and perfused by collagenase to obtain single cardiomyocytes, which was used for recording current of L type voltage I Ca . One hundred to two hundred times of tissue culture infections dose 50 (TCID 50 ) of Coxsackie virus B3 (CVB3) were added to the medium for infection the heart cells (2) Infect BALB/c rats by CVB3: to set up the whole body viral myocarditis models, CVB3 MEM eagle′s solution was injected through intraperitoneal to 4 weeks old BALB/c rats and the hearts were removed after 7 days′ infection for investigating the expression of voltage gate potassium channel (Kv) mRNA (in situ hybridization) and LVDCC α 1 subunit (immunohistochemical methods) All experiments were divided into 3 groups: control group (C), virus infection group (V) and taurine treated group (V+T), in which different dose of taurine was applied Results (1) Taurine could inhibit the Ca 2+ influx at high extracellular calcium concentration in the normal cardiomyocytes and the similar effect could be seen in I Ca Calcium influx and I Ca were increased after CVB3 infection ( P <0 05) and taurine could attenuate the changes and made the membrane potential depolarizing to peak current restored to normal
出处
《中华心血管病杂志》
CAS
CSCD
北大核心
2003年第2期140-144,共5页
Chinese Journal of Cardiology
