Figure 2.

(a) The percentage of time that rats persisted on the rotarod after ischemia compared with the preischemic value as a function of time of stroke. Rotarod test was performed at 2, 7, 14, and 28 days after stroke on the ischemic rats treated with rhVEGF₁₆₅ or saline initiated at 48 hours after ischemia. Treatment with rhVEGF ₁₆₅ (triangles; n = 7) significantly (^AP < 0.05 or ^BP < 0.01) increases time spent on the rotarod compared with the saline-treated group (circles; n = 10). Cerebral vessels and FITC-dextran–perfused cerebral microvessels from the saline-treated rat (b–d) and the rhVEGF₁₆₅-treated rat (e–g) 28 days after the right MCA occlusion. Dorsal view of the right and left hemisphere vessels (b and e), a lateral view of the right hemisphere vessels (c and f), and FITC-dextran–perfused cerebral microvessels in the penumbra of the cortex (d and g). More vessels in the ipsilateral ischemic border zone (e, arrows, and f) and more FITC-dextran–perfused vessels (g) were observed in the rhVEGF₁₆₅-treated rat compared with that in the saline-treated rat (b–d). Bar = 2 mm in f for b, c, e, and f; bar = 200 μm in g for d and g. Rats were decapitated one minute after injection of FITC-dextran and their brains were rapidly removed from the severed heads and digitized at 8× magnification (for panels b, c, e, and f) using an MCID image analysis system (Imaging Research, St. Catherines, Canada). After digitization the brains were placed in 4% paraformaldehyde at 4°C for 48 hours (for panels d and g).