TABLE 1.

Effective doses, their 95% confidence limits, and relative potencies with which cannabinoid CB₁ receptor agonists, cannabinoid CB₁ receptor antagonists, and dopaminergic and opioid drugs decreased schedule-controlled behavior in squirrel monkeys before and during repeated exposure to the cannabinoid CB₁ receptor agonist AM411 (1.0 mg/kg per day)

Italicized data represent significant difference in relative potency values between prechronic versus chronic effects of drugs.

Drug		Prechronic Doses	Prechronic ED50 (95% CL)	Chronic Doses	Chronic ED50 (95% CL)	Relative Potency: Prechronic versus Chronic (95% CL)
		mg/kg	mg/kg	mg/kg	mg/kg
CB1 agonists	AM411	0.01–1.0	0.26 (0.08–5.24)	0.32–100	ND	ND
	AM4054	0.003–0.1	0.02 (0.01–0.07)	0.1–3.2	0.95 (0.32–11.29)	0.02 (0.01–0.04)
	WIN55,212.2	0.032–1.0	0.26 (0.10–1.20)	3.2–32	23.05 (11.81–24.38)	0.01 (0.003–0.028)
	Δ9-THC	0.1–3.2	0.74 (0.33–2.11)	3.2–100	57.27 (22.73–1479.82)	0.02 (0.006–0.065)
	Methanandamide	1–10	NS	10–320	ND	ND
CB1 antagonists	SR141716A	3.2–18	14.27 (10.85–22.01)	0.01–0.32	0.13 (0.04–1273.51)	221 (83.1−715)
	AM4113	1.0–10	5.97 (2.98–53.22)	0.032–1.0	0.25 (0.08–1.72)	31.54 (12.17–102.35)
Indirect DA agonist	Methamphetamine	0.032–0.32	0.20 (0.09–4.80)	0.1–3.2	0.96 (0.44–3.57)	0.26 (0.09–0.90)
DA D1 agonist	SKF82958	0.032–1.0	0.18 (0.09–0.37)	0.032–1.0	0.11 (0.06–0.17)	1.58 (0.83–3.19)
DA D1 antagonist	SCH23390	0.01–0.032	ND	0.01–0.1	ND	ND
DA D2 agonist	R-(−)-NPA	0.003–0.01	0.006 (0.004–0.01)a	0.003–0.1	0.05 (0.03–0.15)	0.18 (0.05–0.49)
DA D2 antagonist	Haloperidol	0.003–0.1	0.04 (0.02–0.07)	0.003–0.32	0.03 (0.02–0.06)	1.19 (0.61–2.49)
Opioid agonist	Morphine	0.32–3.2	1.39 (0.75–3.37)	0.32–10	2.99 (1.36–11.56)	0.52 (0.23–1.12)
Opioid antagonist	Naltrexone	1.0–10	ND	1.0–10	ND	ND

95% CL, 95% confidence limits; DA, dopamine; ND, not determined; NS, nonsignificant regression.

^aSignificant deviation from linearity.