Table 3.
HiS MOR | LoS MOR | HiS SAL | LoS SAL | |
---|---|---|---|---|
Mean (±SEM) saccharin scorea | 13.2 ± 3.0 | 11.0 ± 2.3 | 14.7 ± 2.2 | 8.7 ± 1.7 |
Mean (±SEM) ICSS threshold baseline(μA) for phase 2 (morphine dependence induction) | 152.6 ± 27.1 | 133.3 ± 8.9 | 136.6 ± 29.4 | 136.46 ± 10.0 |
Mean (±SEM) response latency (s) baseline for phase 2 (morphine dependence induction) | 2.7 ± 0.3* | 3.0 ± 0.1 | 2.6 ± 0.1* | 3.1 ± 0.1 |
Mean (±SEM) ICSS threshold baseline (μA) for phase 4 (precipitated withdrawal) | 152.0 ± 25.5 | 136.4 ± 7.6 | 132.1 ± 22.8 | 136.1 ± 8.1 |
Mean (±SEM) response latency (s) baseline for phase 4 (precipitated withdrawal) | 2.7 ± 0.3 | 2.7 ± 0.2 | 2.4 ± 0.2 | 3.1 ± 0.1 |
Saccharin phenotype score = {[24-h saccharin intake (mL)–average water intake (mL)/weight (g)]×100}
Main effect of phenotype (HiS<LoS; p < .05)
HiS = high saccharin rats; LoS = low saccharin rats; MOR = morphine; SAL = saline