Table 1.

Behavioral observations of withdrawal.

Withdrawal behaviors	CTR	CTR + AM281	ACD	ACD + AM281
General hyperactivity	0.17 ± 0.41	0.33 ± 0.52	2.55 ± 0.55**	1.67 ± 0.52
Irritability	0	0.17 ± 0.41	2.83 ± 0.41**	1.17 ± 1.17
Tail tremors	0	0	1.00 ± 0.63*	0.50 ± 0.84
Tail stiffness	0	0	1.67 ± 0.51**	1.00 ± 0.89
General tremor	0	0	1.50 ± 1.05**	0.33 ± 0.52
Spasticity	0	0	2.17 ± 0.75**	0.67 ± 0.82
Wet (dog) shakes	0	0	0	0
Spontaneous convulsive seizures	0	0	0	0
Total withdrawal score	0.17 ± 0.41	0.5 ± 0.55	11.67 ± 1.63***	5.33 ± 1.75

Each sign was assigned a score of 0–3 (0 = not present, 1 = slight, 2 = moderate, 3 = severe). The sum of these scores was used as a quantitative measurement of the severity of the withdrawal reaction, the “total withdrawal score.” *p < 0.05; **p < 0.01; ***p < 0.001 vs CTR.