AQP4 and chronic kidney disease: In CKD rats, AQP4-positive immunoreactivity in the astrocytes and vessels was significantly increased in the hippocampal CA1 and DG regions compared with naïve rats (CKD 10 wks, CA1, F1,14 = 107.55, p < 0.001; DG, F1,12 = 107.55, p < 0.001; one-way ANOVA; Figure 6E,G,(H1),(H2)).