Table 2.

Antagonist dissociation half-lives calculated by different approaches

	Dissociation t1/2 (in min)
Antagonist	‘Two-step competition’	Delayed association	Radioligand dissociation
D2S receptors (Figure 4)
Raclopride	10.3 (8.7–12.1)	13.5	8.9
Spiperone	≫30	≫45	≫120
D2L receptors (Figure 5)
Raclopride	10.2 (8.4–12)	9.2–9.5*	5.8*
Spiperone	≫30	≫45*	≫120*
CB1 receptors (Figure 6)
Taranabant	90 (75–109)		122
Rimonabant	<<60		6.4

Experiments are shown in Figures 4 and 5 or published

^*(Packeu et al., 2008) for the D₂ receptor antagonists raclopride and spiperone and in Figure 6 for the CB₁ receptor antagonists taranabant and rimonabant. Data from the TSC approach were calculated according to Equation 5 based on the obtained values of [LR]_cmax and [LR]_c=0 and knowledge of [L], t', k₁ and k₂ (see Methods). Values in brackets account for a 5% error margin of the [LR]_cmax/[LR]_c=0 ratio. Data from the delayed radioligand association approach were calculated according to Equation 4 by the non-linear regression fitting procedure developed by Malany et al. (2009). Data from radioligand dissociation curves were calculated by non-regression analysis of the curve based on a mono-exponential decline.

TSC, two-step competition.