Fig. 1.

Anatomy of ischaemia-induced brain lesions. Increased GFAP immunostaining in coronal sections of rat brain 4 weeks (A) or 1 year (B) after ischaemia outlines the striatal lesion (star in A). In (B) a rare case with major striatal and cortical tissue loss is shown, with arrowheads indicating the glial scar and arrows the persistent peri-infarct astrogliosis. (Panels C–E) Microphotographs showing immunostained coronal sections, taken from sham-operated young adult (C) and post-ischaemic adult rats, either 5 weeks (D) or 1 year (E) after the insult. A gradient in the numbers of mitotic cells from dorsal (high) to ventral parts (PH3 + cells are indicated by white arrows) is observed in sham-operated animals. Ischaemia induced an increase in the numbers of PH3 + cells, especially within the areas of the tissue directly affected by injury (delineated by the pale yellow lines in D and E). (Panel F) Microphotograph showing a high magnification detail of the SEZ. Mitotic cells within the niche were immunopositive for PH3 (green in F2) and were distinguished in neural stem cells (arrow) or progenitors (arrowhead) depending on co-expression of GFAP (red). (Panel G) Microphotograph showing a high magnification detail of a mitotic cell (PH3 + in red) co-expressing Dcx (in green); thus being a neural progenitor [scale bar: 2 mm in A, B; 100 μm in C–E, 10 μm in panel F and 10 μm in G].