Histology after intra-arterial cell infusion in rats. (A) T2-weighted coronal slices from a rat infused with 0.5 × 106 cells in 0.5 ml within 3 minutes. The white boxed region reveals a typical microembolism. Nissl staining (B), silver staining (C), and IgG staining (D) show the pathologic changes in the boxed region. Scale bar in (A) is 2 mm, and for (B)-(D) is 250 μm.