Figure 3.

Efficacy of the vaccines containing the F_8–10 haptens against fentanyl. Sprague–Dawley rats (n = 6, each group) were given an intramuscular (i.m.) vaccination on days 0, 21, 42, and 63 with conjugate vaccines containing the F₁ and F_8–10 haptens or with CRM control, and were then challenged with 0.1 mg/kg fentanyl, subcutaneous (s.c.). Rats were monitored at 15 min intervals for (A) antinociception by latency to respond on a hot plate and for (B) oxygen saturation (%) and (C) heart rate measured by pulse oximetry. Data are expressed as mean ± SEM. Below their respective graphical panels, significance of each vaccine group vs CRM control is indicated at each time point. Symbols: *p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001 compared to control; exact p-values are listed for 0.05 ≤ p ≤ 0.1; and “–” indicates no significant difference, 0.10 ≤ p.