Figure 10.

Effects of co-administration of EU93-108 and morphine on tolerance development in (A) male and (B) female mice. Mice received vehicle and saline (blue circles), vehicle and morphine (green circles), ifenprodil and morphine (purple circles), or EU93-108 and morphine (yellow circles). Naïve indicates latencies prior to the first morphine dose. Day 1 indicates latencies after first morphine dose, and day 4 indicates latencies after final morphine dose once tolerance has developed. Each circle represents n = 8 mice, and data are presented as mean ± SEM.