Fig 1. Dose responses of epidural administration of ropivacaine both in mesylate injection and sustained release suspension form on motor paralysis duration (A) and latency (B) in rats.

Data are presented as means ± SEM (n = 6 in each group). ^a denotes statistically significant difference of ropivacaine sustained release suspension compared to the ropivacaine mesylate group (P < 0.05 by a two-way repeated-measures ANOVA followed by a post-hoc Student-Newman-Keuls test).