CIA enhances microvascular pathology in APP/PS1 mice. (A) Bright-field photomicrographs showing microvascular pathology in the cerebral cortex (Cor, top row) and hippocampus (Hip, bottom row) immunolabeled with collagen-IV 4 months after treatment of 2-month-old wild-type (Tg-) and APP/PS1 (Tg+) mice with vehicle or CIA. Scale bar = 200 μm. (B) Analysis of vessel density and length in the cerebral cortex and hippocampus (Tg- vehicle, n = 3; Tg- CIA, n = 3; Tg+ vehicle, n = 3; and Tg+ CIA, n = 4). (C) High-power photomicrographs showing microvascular pathology in the cortex of CIA-treated Tg+ mice. Note thinner vessel (arrow), string vessel (arrowhead), and degenerating vascular segments (open arrow) in Tg+ CIA compared with vehicle. Scale bar = 50 μm.