Figure 4: Effect of L-NAME and 1400 W on the inflammatory and hypernociceptive effects of zymosan in TMJ. Zymosan (2 mg; 40 μL) or saline was injected i.art. into the left TMJ of the rat. L-NAME (100 mg/kg) or 1400 W (1 mg/kg) was injected (i.p.) 30 min before zymosan. The mechanical nociceptive threshold was measured in L-NAME- (a) and 1400 W-treated (b) animals before and 4 h after an i.art. injection of zymosan or saline. After 6 h, leukocyte migration was evaluated in L-NAME- (c) and 1400W-treated (d) animals by cell counting in TMJ fluid. MPO activity from TMJ fluid in L-NAME- and 1400 W-treated animals (e). MPO activity in TMJ tissues in L-NAME- and 1400W-treated animals (f). Plasma extravasation following an i.art. injection of zymosan or saline in L-NAME- and 1400 W-treated animals (g). Data are expressed as means ± SEM (). versus Sham. versus zymosan (ANOVA, Bonferroni).