Figure 2.

Transcriptional response and morphological changes following nucleus accumbens (NAc) infarct across time. A, Time-dependent expression of genes associated with endothelial cells (Pecam1; sham: day [D] 3: P=0.0027; D7: P≤0.0001; and D14: P=0.0005; ET-1 (endothelin-1): D3: P=0.5992; D7: P≤0.0001; and D14: P=0.0001), tight junctions (Cldn5: ET-1: D7: P=0.0005 and D14: P=0.0007; Ocln: ET-1: D14: P≤0.0001; Tjp1: sham: D3: P≤0.0001; D7: P=0.9822; and D14: P≤0.0001; and ET-1: D3: P≤0.0001; D7: P=0.6415; and D14: P≤0.0001), astrocyte reactivity (Gfap: ET-1: D7: P≤0.0001), and angiogenesis (Vegfa) in sham (left) or ET-1–injected mice (right). The dotted line represents normalized gene expression vs 1 day post-surgery for each gene. B, Gene expression of sham or ET-1–injected mice normalized to naive animals that did not undergo surgery (dotted line) for Pecam1, Cldn5, Ocln, Tjp1, Gfap, and Vegfa blood-brain barrier–related genes with significant effects for sham: Pecam1 (2-way ANOVA: surgery effect: P≤0.0001), Gfap (2-way ANOVA: surgery effect: P=0.0080), Vegfa (2-way ANOVA: surgery effect: P=0.0238), ET-1: Pecam1 (2-way ANOVA: stroke effect: naive vs ET-1: P=0.0011; stroke effect: sham vs ET-1: P=0.0003), and Vegfa (stroke effect: sham vs ET-1: P=0.0274). C, Immunostaining of Cldn5 (claudin-5) with the CD31 (cluster of differentiation 31) endothelial cell marker in sham vs ET-1–injected mice. Protein levels were normalized on naive animals, and an increase in Cldn5/CD31 ratio was noted for the ET-1 group at 7 and 14 days poststroke (2-way ANOVA: stroke effect: P=0.0185; n=3–4/group). D, Triple immunostaining with the cell-specific markers NeuN (neuronal nuclei), Gfap (glial fibrillary acidic protein), and Iba-1 (ionized calcium-binding adapter molecule 1) for neurons, astrocytes, and microglia, respectively, revealed gliosis in the NAc of ET-1–injected mice. Data represent mean±SEM. Two-way ANOVA followed by the Tuckey multiple comparison test was applied with ****P≤0.0001, **P≤0.01, and *P≤0.05.