Furthermore, the A1 astrocytic marker C3 was obviously upregulated in the hippocampal areas of the middle-aged mice with hypertension compared with the very weak expression of C3 in the control group (31.14 ± 4.01% vs. 81.42 ± 3.33%, p < 0.01, DG; 17.71 ± 2.42% vs. 92 ± 4.84%, p < 0.01, CA1; 21 ± 2.3% vs. 56.71 ± 2.81%, p < 0.01, CA3). This evidence concerns the gene C3 and hypertensive disorder.