Table 1.

F-ratios and p-values comparing the slope of the control dose response curve (i.e. Δ⁹-THC alone) to that for Δ⁹-THC determined in the presence of a dose of test compound, as well as ED₅₀ values, potency ratios, and corresponding 95% confidence limits (95% CL), in monkeys discriminating Δ⁹-THC (0.1 mg/kg i.v.)

Test drug	Slope: Δ9-THC alone compared with Δ9- THC + test compound	ED50 value in mg/kg	Potency ratio (95% CL)†
Δ9-THC alone		0.042 (0.031–0.060)
+ Rimonabant (1 mg/kg)	Not different	0.45 (0.34–0.65)	11 (8.1–16)*
+ Cocaine (1 mg/kg)	Not different	0.10 (0.054–0.30)	2.5 (1.4–4.4)*
+ Cocaine (3.2 mg/kg)	F1,19=20; p<0.001	0.32***	NA
+ Amphetamine (0.32 mg/kg)	Not different	0.14 (0.083–0.32)	3.3 (1.4–4.4)*
+ Amphetamine (1 mg/kg)	F1,22=24; p<0.001	0.32***	NA
+ Bupropion (3.2 mg/kg)	Not different	0.070 (0.049–0.10)	1.7 (0.9–2.4)
+ Bupropion (10 mg/kg)	F1,18=4.0; p<0.05	0.32***	NA
+ RTI 113 (1 mg/kg)	F1,22=14; p<0.01	0.32***	NA
+ RTI 177 (3.2 mg/kg)	F1,25=17; p<0.001	0.32***	NA
+ Haloperidol (0.0032 mg/kg)	Not different	0.046 (0.031–0.063)	1.1 (0.73–1.6)
+ Haloperidol (0.01 mg/kg)	Not different	0.021 (0.015–0.030)	0.52 (0.35–0.78)**
+ Imipramine (3.2 mg/kg)	Not different	0.081 (0.047–0.16)	1.9 (0.9–3.3)
+ Imipramine (10 mg/kg)	Not different	0.088 (0.054–0.19)	2.1 (1.1–3.2)*
+ Desipramine (17.8 mg/kg)	Not different	0.066 (0.046–0.094)	1.6 (1.0–2.5)

^†Potency ratios and 95% confidence limits are the ED₅₀ value of Δ⁹-THC determined in the presence of the test drug divided by the control ED₅₀ value of Δ⁹-THC NA, not applicable, i.e. slopes were significantly different

^*Significant decrease in the potency of Δ⁹-THC

^**Significant increase in the potency of Δ⁹-THC

^***The ED₅₀ value is the largest dose that did not decrease response rate to less than 20% control