Analysis of vascular senescence. End.p53-WT mice aged 12 weeks (adult) or 12 months (aged) were histologically examined for signs of vascular aging, such as (A) the total vein perimeter and the number of (B) total cell nuclei and (C) TUNEL⁺, apoptotic cells lining the vein lumen. Graphs show individual values as well as the mean ± standard error of the mean (SEM) per group. *P < .05. (D) Representative images after staining with MTC (top and middle row; asterisks indicate the IVC; arrows point to cell nuclei) or TUNEL (bottom row; arrowheads point to apoptotic cells [pink signal]). Scale bars represent 200 µm (top row) or 20 µm (middle and bottom row). (E) Confocal microscopy images after dual immunofluorescence staining of the IVC from End.p53-WT and End.p53-KO mice 12-week-old (adult) or 12-month-old (aged) for CD31 and p53. Cell nuclei were visualized using DAPI. Scale bars represent 10 µm.