Figure 4: Clustering analysis of the differentially expressed genes in the rabbit basilar artery after SAH. Combined hierarchical clustering was applied to expression data of all differentially expressed genes (1,121 genes; 2.57% of all genes). Heat map representation of gene expression profiles. Each line across the map represents a single gene. Each column represents an array of genes (from day 0 to day 7). The number following the hyphen is the sample number (each time point has three numbers: 1, 2, and 3). Gene expression values were log2 transformed and median centered for each gene. The relative gene expression level is indicated by color and ranges from highly increased (intense red) to highly decreased (intense green), with black representing unchanged expression.