Effect of cycloheximide administration on bupivacaine-induced acute muscle degradation.

We have examined the effect of cycloheximide on bupivacaine-induced, macrophage-mediated muscle degeneration in rats and obtained the following results. Direct intramuscular injection of bupivacaine into soleus muscle caused uniform muscle degeneration (Ishiura, S. et al. (1983) J. Biochem. 94, 311-314). The degeneration was most prominent 48 h after injection, with many infiltrating macrophages. Intraperitoneal administration of cycloheximide prevented the bupivacaine-induced macrophage invasion and decrease of structural proteins 48 h after injection. Cycloheximide inhibited the increase in lysosomal enzymes in bupivacaine-treated muscle. The peritoneal macrophages increased in number immediately after bupivacaine injection, while cycloheximide inhibited their accumulation. These results indicated that cycloheximide inhibited muscle degradation by preventing macrophage proliferation.