γ-Acetylcholine Receptor Mediating Dynamic Changes of Resistance to Rocuronium in the Denervated Skeletal Muscle.

ABSTRACT

BACKGROUND/AIMS: Denervation resulted in resistance to non-depolarizing muscle relaxants (NDMRs), the magnitude of which changed after denervation in the skeletal muscle. The aim of this study was to investigate whether changed potencies of rocuronium were due to altered γ-acetylcholine receptor (γ-AChR) expression after skeletal muscle denervation. METHODS: Innervated and denervated muscle cells were used in this study. Patch clamp and Western blotting techniques were separately applied to examine IC50 values of rocuronium and γ-AChR protein expression at different times after denervation. Then, using the linear Pearson correlation analysis, the relationship between IC50 values of rocuronium and γ-AChR expression was tested. RESULTS: Compared with the innervated control, both IC50 values of rocuronium and γ-AChR expression significantly increased at Day 4, 7, and 14 after denervation in the skeletal muscle. Furthermore, γ-AChR protein and IC50 values of rocuronium exibited a significant positive correlation (r = 0.7678, p < 0.0001). CONCLUSION: These above results indicated that dynamic changes of resistance to NDMRs may be due to altered γ-AChR expression after skeletal muscle denervation.