Figure 4.

Effects of antibodies against EM-1 (anti-EM-1), EM-2 (anti-EM-2), and β-endorphin (anti-END) injected (intraplantarly) into inflamed paws on swim stress-induced antinociception. Left, Dose dependency of anti-opioid peptides injected separately (p = 0.007 for anti-EM-1; p = 0.002 for anti-EM-2; p < 0.001 for anti-END, ANOVA, linear regression). Right, Comparison of single injections of anti-END, anti-EM-1, and anti-EM-2 with concomitant injection of anti-EM-1 and anti-EM-2. * indicates significant differences versus control, and ⁺ indicates significant differences versus anti-END (p < 0.05, Bonferroni’s test). Data are means ± SEM.