Table 1:
Percentage of rats showing normal and abnormal behavior following deltorphin microinjection into the vPAG in morphine-pretreated rats.
Crouching/lying
Pretreatment
25–39 minutes
40–54 minutes
Saline
0% (0/6)
0% (0/6)
Morphine 10 mg
20% (1/5)
67% (6/9)
Morphine 20 mg
36% (4/11)
40% (6/15)
Note: sample sizes are shown in parentheses.