Table 2.

Selective ligands for the dopamine D4 receptor

Ligand	Affinity for D4 (nM)	Specific purposes, uses, applications
L-745,870	0.43–0.51	In vivo administration in rodents for functional, behavioural and drug-dependence studies [177–179]; development of PET radioligands [180]; in D4 receptor-overexpressing cell systems [52, 181]; tests for antipsychotic activity [120, 182]
L-741,742	3.5	In vivo administration to mice for anxiety testing [183]
ABT 724	~45–65	In vivo administration to rats to test potential treatment of erectile dysfunction [184, 185]
WAY 100635	16.4	D4 receptor agonist and 5HT1A antagonist; produces discriminative stimulus effects in rats [186, 187]
PD 168077	8.7	Selective D4 agonist, proerectile effect in rats [188]; tested in mice for memory consolidation studies [189]
PNU 96415E	3	Tested for antipsychotic potential [190]
Ro 10-5824	5.2	Selective D4 agonist, increases novel exploration in mice [191]
NGD 94-1	3	In vivo administration to monkey for cognitive and memory tests [192]; in vitro autoradiography studies [193, 194]
NRA 0160	0.5	Tested for antipsychotic activity in animal models [195, 196]
CI 1030	4.3	Tested for antipsychotic activity in animal models [195, 196]
A-412997	7.9	D4 receptor agonist; improves cognitive performance and stimulates motor activity in rats [197]