Inhibition of the migration of SCs and neurite outgrowths in DRGs by high glucose levels. Under a phase contrast microscope, the each SC migration outline was indicated by a bright field. The dashed line shows the SC outline. (A) The SC outline size decreased as the glucose concentration increased at the same culture times, but this effect was not totally inhibited high glucose. Also, the SC migration outline expanded in various glucose media as the culture time increased from 3 to 11 days (B). When the SCs were treated with Ara-C, the neurite outgrowth decreased slowly as the glucose concentration increased (C and D) at the same culture times, but this effect was not totally inhibited high glucose. The neurite outgrowth increased in various glucose media as the culture time increased from 3 to 11 days. *P < 0.05 (25 mM vs. 5.5 mM); **P < 0.01 (B: 55 mM and 25 mM versus 5.5 mM; D: 55 mM vs. 5.5 mM).