fig3

Figure 3. Experimental efficacy of electrostimulation and tacrolimus (FK506) in nerve regeneration. (A) GFP+ axon outgrowth was observed 14 days after repair. Electrostimulation (ES) groups displayed GFP+ axon growth that appeared more organized and unidirectional, with long axon projections extending through the distal nerve. Yellow arrows indicate the repair site; white scale bar represents 1 mm; (B) GFP+ axon outgrowth was quantified using GFP+ axon density measured at discrete spatial regions distal to the repair site. All data represented as mean ± SD, n = 4 per group. * indicates P < 0.05 10 min ES vs. 0 min ES, # indicates P < 0.05 60 min ES vs. 0 min ES, ^ indicates P < 0.05 10 min ES vs. 60 min ES. The dotted line indicates the average GFP+ density of the proximal nerve. (Adapted from Roh et al., 2022)^[69]; (C) Rate of regenerating axons after crush injury in mice treated with FK-506. Taking the difference between the length measurements at each timepoint via in vivo serial transcutaneous imaging, an average rate of axonal regeneration was calculated for each experimental group. Both FK-506 preload groups exhibited a rate of regeneration that was significantly greater than all other experimental groups. The rate of regeneration in the control group at ~3 mm/day is consistent with reported rates in the literature. (P < 0.005 for comparison between indicated experimental groups) (Adapted from Yan et al., 2011)^[79].