Table 4.

Effects of clonidine on somatic nicotine withdrawal signs.

Clonidine (μg/kg)		vehicle	10	20	40
Abd. const.	Saline	0.1 ± 0.1++	0.1 ± 0.1++	0.3 ± 0.3++	0.3 ± 0.2++
	Nicotine	3.8 ± 1.5	4.3 ± 0.8	4.8 ± 0.8	4.9 ± 0.9
Eye blinks	Saline	5.4 ± 0.8++	4.1 ± 0.5++	3.0 ± 0.7	4.8 ± 1.0
	Nicotine	22.0 ± 3.4	13.0 ± 3.5**	6.6 ± 1.8**	6.1 ± 2.4**
Ptosis	Saline	0.3 ± 0.3++	0.4 ± 0.4+	0.8 ± 0.5	2.3 ± 1.0 +
	Nicotine	3.1 ± 0.6	2.1 ± 0.7	1.0 ± 0.5*	0.3 ± 0.3*
Facial fasc.	Saline	0.0 ± 0.0++	0.0 ± 0.0++	0.0 ± 0.0++	0.0 ± 0.0++
	Nicotine	5.3 ± 1.1	4.1 ± 1.1	4.4 ± 1.5	4.8 ± 0.8
Yawns	Saline	0.1 ± 0.1	0.1 ± 0.1	0.0 ± 0.0	0.0 ± 0.0
	Nicotine	0.2 ± 0.1	1.1 ± 0.6	0.2 ± 0.2	0.2 ± 0.2
Shakes	Saline	0.9 ± 0.5	0.0 ± 0.0+	0.0 ± 0.0	0.0 ± 0.0
	Nicotine	1.4 ± 0.5	1.0 ±0.3	0.2 ± 0.1	0.1 ± 0.1*
Other signs	Saline	0.1 ± 0.1	0.1 ± 0.1	0.4 ± 0.3	0.6 ± 0.4
	Nicotine	0.0 ± 0.0	0.4 ± 0.2	0.5 ± 0.2	0.4 ± 0.3

Somatic signs in nicotine-treated (n = 10) and saline-treated rats (n = 8) as recorded during 10-minute observation periods. Abdominal constrictions include gasps and writhes; facial fasciculations include cheek tremors and teeth chattering; shakes include head shakes and body shakes; other signs include escape attempts and genital licks.

Plus signs (+ P<0.05, ++ P<0.01) indicate fewer somatic signs in the saline group than in the nicotine group.

Asterisks (* P<0.05, ** P<0.01) indicate a decrease in the number of somatic signs compared to rats in the same treatment group (nicotine) and acutely treated with vehicle. Data are expressed as means ± SEM.