Hierarchical clustering revealed specific patterns induced by each treatment. Hydralazine, valproic acid and the combination down-regulated a similar set of genes. On the contrary, up-regulated genes were distinctive for each treatment. From 1,281 differentially expressed genes, 651 were up-regulated and 630 down-regulated. The number of genes over-expressed specific of hydralazine, valproic acid and the combination were 153, 178 and 352. Each row represents a gene, whereas each column corresponds to the treatment drug. The relative abundance of the gene in the tissue correlates with color intensity; red induced; green repressed; black no change. H: hydralazine, V: valproic acid, and HV: hydralazine and valproic acid.