FIG. 2.

(A) Analysis of mechanical allodynia, as described in Figure 1 and in the methods section. (A) Incidence of pain. Animals that had increased sensitivity in both forelimbs at all time points tested were considered to demonstrate persistent pain. None of the sham animals had persistent pain, while 8% of vehicle-treated spinal cord injury (SCI) rats and 34% of VEGF₁₆₅-treated animals had persistent pain. The chi square test showed a statistically significant difference between VEGF₁₆₅-treated and vehicle-treated SCI rats (*p < 0.05). (B) Pain levels. Shown are the percentage decreases in mechanical thresholds seen at 4, 6, and 8 weeks post-SCI in rats that developed persistent allodynia. Although the percentage decrease is represented by negative numbers in Figure 1, here we present it as a positive number (on the y axis), so a higher percentage indicates increased sensitivity (e.g., lower thresholds to mechanical stimuli or increased pain levels in post-SCI rats compared to pre-injury baseline levels). (C) Basso, Beattie, and Bresnahan (BBB) scale scores (mean ± standard deviation) of all SCI rats used in this study showed no effect of VEGF₁₆₅ administration on motor recovery after SCI (VEGF, vascular endothelial growth factor).