Effect of intravenous bone marrow stromal cells (BMSCs) on early and late phases of mechanical hypersensitivity after tendon injury. BMSCs were infused at 3 days (A) or 2 and 4 months (B) after tendon ligation (TL; MSC-TL). Rats receiving sham operation (MSC-Sh) also was infused with BMSCs at 3 days after the surgery. There were significant increases in EF50s after BMSC infusion. Asterisks denote significant differences versus 3 day-TL/Sh or 2/4 months TL: *, p < .05; **, p < .01; ***, p < .001. Cross signs denote significant differences versus medium: +, p < .05; ++, p < .01; +++, p < .001. Error bars represent 95% confidence intervals of EF50s. Abbreviations: Sh, sham; TL, tendon ligation.