Pericyte expression of miR-145. (a) To differentiate between pericyte and EC expression, vascular fragments were isolated from the brains of pericyte-deficient Pdgfbret/retmice using anti-CD31-coated magnetic beads. Bars show relative expression levels in CD31+ fragments from wild-type and Pdgfbret/ret± standard error of the mean (n = 4 and 3, respectively). (b) CD31+ cells were isolated from EB cultures using magnetic beads. After depletion of CD31+ cells, cells expressing the pericyte marker NG2 were isolated using the same protocol. Bars show the ratio of expression between NG2+ and CD31+ fragments. Error bars indicate standard error of the mean (n = 3). (c-i) In situ hybridization (blue) against miR-145 (c, e-h) and miR-126 (d) with double staining for NG2 (green) (e, g-h). (c) miR-145 in situ hybridization stains vascular smooth muscle cells (m, media) whereas (d) miR-126 stains ECs (arrowheads) in kidney artery (scale bar, 25 μm). (e) High power magnification of a small vessel in kidney shows that a miR-145-positive cell (arrow) expresses NG2 (scale bar, 5 μm). (f) miR-145 in situ hybridization labels solitary cells in adult brain (arrows; scale bar, 100 μm). (g) Double staining for miR-145 (arrows) and NG2 show co-expression in cells tightly associated with small caliber (10 μm) capillaries in brain (scale bar, 50 μm). (h) miR-145 staining in the heart is confined to arterioles (arrowheads) whereas no expression was detected in NG2-positive cells in microvessels (arrows) (scale bar, 50 μm). (i) Negative control (without probe; scale bar, 100 μm).