去卵巢和雌激素替代治疗对心肌细胞基因表达谱的影响

Influence of ovariectomy and estrogen replacement on gene expression profile of myocardium in rats

目的:本实验通过高通量的cDNA微阵列技术,研究去卵巢和雌激素替代治疗对心肌细胞基因表达谱的影响,寻找雌激素的靶基因。方法:用1400个基因构建的cDNA微阵列检测假手术组(Ⅰ)、去卵巢组(Ⅱ,去势组)和雌激素替代治疗组(Ⅲ,替代组)3组SD雌鼠心肌组织的基因表达差异,随机选2个基因用半定量RT-PCR验证检测结果。结果:假手术组和去势组共检出心肌差异表达的基因177个,其中去卵巢导致上调的基因91个,下调的基因86个;去势组和替代组共检出心肌差异表达的基因164个,其中雌激素替代治疗后导致上调的基因113个,下调的基因54个。Ⅰ/Ⅱ和Ⅲ/Ⅱ比较,相同的差异表达基因54个,雌激素明显影响心肌膜通道和载体(18个)、细胞受体(9个)、信号转导相关基因(7个)和细胞代谢(6个)的mRNA水平。而大部分基因(45个)是在去势组表达下调,在雌激素替代组表达上调。RT-PCR实验证实了cDNA微阵列结果。结论:长期雌激素替代治疗明显影响心肌细胞膜通道和载体、信号转导、细胞受体和细胞代谢等相关基因的表达。长期雌激素替代治疗可通过增加Na+,K+-ATPase和Na+/H+交换蛋白的基因表达,稳定心肌细胞内Na+和K+的浓度。雌激素还可抑制多巴胺受体基因的表达,预防心肌肥大、充血性心衰等心脏疾病的发生。

AIM： To investigate the influence of ovariectomy and estrogen replacement treatment on profile of gene expression in myocardium by cDNA microarray, and to characterize the targeting genes of estrogen. METHODS ： cDNA microarray containing 1 400 rat cDNAs was used to study the genes differentially expressed in myocardium between sham （ Ⅰ ）, ovariectomy （ Ⅱ , OVX） and estrogen replacement treatment （ Ⅲ, OVX ＋ E2） group. Then down -regulated genes in myocardium of OVX rats were further confirmed by RT - PCR. RESULTS： 177 genes were differentially expressed in myocardium between sham and OVX rats, with 91 genes up -regulated and 86 genes down- regulated in OVX rats.. 164 genes were differentially expressed in myocardium between OVX and OVX ＋ E2 rats, with 113 genes up -regulated and 54 genes down - regulated in OVX rats. There were 54 genes differentially expressed in OVX compared to sham and OVX ＋ E2. They are involved in membrane channels and transporters （18）, cell receptors （9）, intracellular transducers/effectors/modulator （7） and metabolism （6）. Most of the genes （45） were down - regulated in OVX rats and up - regulated in OVX ＋ E2 rats. RT - PCR test confirmed the results of cDNA microarray. CONCLUSIONS： Long - term estrogen replacement may influence the expression of genes involved in membrane channels and transporters, cell receptors, intracellular transducers/effectors/modulator and metabolism. Long - term estrogen replacement has some beneficial effects on ionic concentration and cardiac function which partially comes from the results of influence of expression on Na^＋ , K^＋ - ATPase and Na^＋/H^＋ exchanger. Estrogen has an inhibitory effect on the expression of dopamine receptor, which partially clarify the myocardial protection of estrogen.