Fig. 3.

Reversal of perisciatic SIN-induced mechanical allodynias by intrathecal CNI-1493, a p38 mitogen-activated kinase inhibitor. Rats were assessed for low-threshold mechanical sensitivity (von Frey test) both before (baseline) and 13, 15, 17, and 19 hr after completion of perisciatic drug administration. Replicating and extending our earlier studies (Chacur et al., 2001; Gazda et al., 2001), low-dose zymosan induced a unilateral allodynia (A), whereas high-dose zymosan induced a bilateral allodynia (B) at 13 hr after injection. CNI-1493 reversed both of these allodynias, although it had no effect on behavior in the absence of perisciatic zymosan (A).