Figure 3. In vivo characterization of EPC angiogenesis. (A) Serial laser speckle blood flow imaging revealed that the ischemic hindlimbs of aged mice exhibited lower perfusion signals than those of younger mice. (B) The ratio of ischemic to normal blood flow decreased with aging. (C) On postoperative day 14, immunostaining was conducted to evaluate the capillaries in non-ischemic and ischemic thigh adductor muscles. (D) Quantitative analyses revealed that aging reduced the capillary density in both non-ischemic and ischemic muscles. *P<0.05. n=5. Y, young; MA, middle-aged; A, aged. Scale Bar: (C) 100 μm.