cDNA array hybridization reveals cardiac gene expression in acute ischemic murine hearts

Although cDNA array technique has recently become available in the cardiovascular field, it has not yet been established what kind of genes in the myocardium are expressed by acute ischemia. Since many substances contribute to the pathophysiology of acute ischemic hearts, we investigated transcription responses of murine hearts to ischemia using cDNA array representing 18,376 genes.

In 29 male mice, we ligated the proximal site of the left coronary artery for 60 min. In 14 mice, we performed the sham operation without the ligation of the left coronary artery. After 60 min, the hearts were excised to obtain mRNA, and we performed cDNA array analysis. In 18,376 cDNA, 2 known genes were upregulated over 10-fold, 11 known genes were upregulated 5.0- to 9.9-fold, and 32 unknown genes were upregulated over 5.0-fold compared to sham-operated controls. In contrast, 11 known genes and 7 unknown genes were downregulated to levels below 0.2-fold. For 9 of the 13 known genes of which expression was increased as analyzed by cDNA array, subsequent Northern blot analysis also revealed an increase in expression.

Using cDNA array analysis we found that cardiac expression of 24 known and 39 unknown genes was modulated by acute ischemic stress, and appeared to be related to the pathophysiology of ischemic hearts. These results show that cDNA array analysis may provide a new molecular insight to the pathophysiology of acute ischemic hearts.