(a) Claudin-5 was expressed in hippocampal microvessels derived from both young adult and reproductive senescent females, however claudin-5 expression was brighter and more junctional in microvessels from young adults as compared to those from reproductive senescent females. (b) Histogram represents the average (±SEM) composite rating scores for continuity and junctional localization for claudin-5. Estrogen treatment (closed bars) did not affect the ratings scores in either young adult or senescent females. (c) Western blot analysis showed no change in claudin-5 expression between young adults and reproductive senescent females. N=4–5 per group, 6 vessels were rated per animal, * P<0.05. Key: YA: young adult, RS: reproductive senescent, O: ovariectomized and replaced with control pellet, E: ovariectomized and replaced with estrogen pellet. Bar=50 µm.