Fig. 6. ATP--S, but not ADP, enhances epithelial wound closure. (A,B) Growth-factor-starved THCE cells were wounded with a single tooth of a 48-well sharkstooth comb for DNA sequencing gels. Cells were allowed to heal in KBM containing 100 µM ADP or 100 µM ATP--S. Wound closure was photographed immediately after wounding (0 h) or 6 hours post wounding (6 h). Micrographs (A) represent one of three samples performed each time. Statistical analysis (B) indicates healing extent. Values are expressed as the mean ± s.e.m. (n=3), ^**P<0.01.