摘要
目的 利用“2肾 1夹”型Goldblatt高血压大鼠模型 ,观察在高血压形成过程中与心房肌电重构相关的离子通道mRNA的变化 ,探讨其意义。方法 Sprague Dawley大鼠 ,高血压组用U型银夹夹住左肾动脉近心端 ,右肾保留 ;假手术组只分离左肾动脉 ,不夹银夹。套尾法监测尾动脉血压 ,分别于手术后 2、4、6w处死动物 (各 6只 ) ,TRIZOL提取左右心耳总mRNA ,RT PCR半定量分析Na+ 通道α亚单位 (Na+ α)、L型钙通道α1C亚单位 (CaL α1C)和瞬时外向钾通道 (Kv4 3)mRNA的表达量 (以GAPDH为内参照 )。结果 在高血压形成过程中 ,左心耳CaL α1C的mRNA水平在 2w和 4w明显增高 ,分别是假手术组的 2 5倍和 2 4倍 (P <0 0 0 1) ,6w恢复正常 ,右心耳在 2w和 4w无明显变化 ,6w为假手术组的 2 5倍 (P <0 0 0 1) ;左心耳Kv 4 3的mRNA水平在 4w和 6w分别是假手术组的 1 9倍和 1 7倍 (P <0 0 0 1) ,在右心耳却呈下降趋势 ,4w和 6w分别降低了 30 % (P <0 0 5 )和 2 0 % (P =0 10 ) ;Na+ α的mRNA在左右房无明显变化。结论 肾性高血压大鼠在高血压形成过程中 ,心房肌CaL α1C的mRNA水平表现为上调 ,左房明显早于右房 ,左右房Na α和Kv 4 3的mRNA变化明显不平行 ;提示mRNA水平的变化是电重构的基础 ,并可能进一步导致?
Objective We observed the mRNA changes of Na + channel α subunit(Na-α), L-type Ca 2+ channelα 1C subunit (CaL-α 1C ), and Kv4.3 in the atria of Goldblatt hypertensive rats, to investigate the significance in atrial electrical remodeling at mRNA level. Methods Two-kidney one-clip (2K1C) hypertensive Sprague-Dawley rats were sacrificed at 2 nd , 4 th , 6 th week after operation, sham-operated rats served as control. Total mRNA of right auricle (RA) and left auricle (LA) was extracted respectively by use of Trizol reagent. Semiquantitative RT-PCR was used to estimate the changes of mRNA of Na-α, CaL-α 1C , and Kv 4.3, and GAPDH was used as internal control. Results mRNA level of CaL-α 1C ,in LA increased to 2.5 and 2.4 times at 2 and 4 week ( P <0.001), and down to normal level at 6 week, while in RA, it increased to 2.5 times of sham only at 6 week ( P <0.001). mRNA level of Kv 4.3, in LA increased to 1.9 and 1.7 times of sham ( P <0.001), while in RA, it decreased by 30% ( P <0.05), 20% ( P =0.10) at 4, 6 week, respectively. No change in the level of Na-α channel mRNA comparing with sham, but Na-α mRNA was less in RA than LA at 2 week ( P <0.05). Conclusion The mRNA level in CaL-α 1C up-regulated in the atria of 2K1C hypertensive rats, the changes in LA are more markedly than in RA. The mRNA changes of Na-α, CaL-α 1C and Kv4.3 were not parallel between LA and RA. It suggested that mRNA change is basis of electrical remodeling, and may play a role in the genesis of atrial arrythmias in hypertensive heart.
出处
《高血压杂志》
CSCD
2003年第3期229-233,共5页
Chinese Journal of Hypertension
关键词
高血压
电重构
MRNA
hypertension
electrical remodeling
mRNA
