Table 3.

The dose of each drug in milligrams per kilogram (95% CI in parentheses) that reduced response rates to 50% of saline response rates for each group

	0.1 pram vs. saline	1.0 sum vs. saline	0.1 pram vs. 1.0 sum or saline	1.0 sum vs. 0.1 pram or saline
Pramipexole	0.11 (0.040 to 0.64)	0.18 (0.051 to 0.70)	0.28 (0.094 to 1.0)	0.19 (0.080 to 0.49)
Sumanirole	1.8 (0.40 to 9.1)	4.1 (0.52 to 66)	4.0 (1.2 to 19)	2.8 (0.85 to 11)
Quinpirole	0.024 (0.0062 to 0.10)	0.12 (0.030 to 1.17)	Not tested	0.040 (0.014 to 0.15)
7-OH-DPAT	0.037 (0.013 to 0.12)	0.040 (0.016 to 0.11)	Not tested	0.046 (0.010 to 0.36)
Cocaine	n.s.	n.s.	Not tested	n.s.

Cocaine did not reduce response rates to 50% of control values in any group.

pram Pramipexole, sum sumanirole, n.s. not significant linear regression analysis.