HMGB1 and hydrops fetalis: The increased levels of HMGB1 and CGRP in the inflamed paw tissues of rats subjected to CCI of the sciatic nerve are reduced significantly following 3 days of HFES, whereas no significant changes are observed in substance P levels (HMGB1: sham surgery = 16.5 ± 1.4 ng/mg protein, CCI = 34.0 ± 1.8 ng/mg protein, CCI + HF stimulation = 16.5 ± 2.7 ****ng/mg protein, ****P < 0.0001 vs. CCI group, N = 8 per group.