Figure 10.
Comparison of the survival rate between the groups of animals (n = 20 per group) following the highest doses of fentanyl (60 mg/kg ip). Survival was significantly lower in β-arr2-deficient mice (χ2 test P = 0.008). Note that all animals that died stopped breathing within 10 min. All mice that were alive at 15 min survived the 1-h experiment. Arrb2tm1Rjl, Arrb2 knockout mice.