TABLE 2.

Binding affinities for selected histamine receptor ligands

Compound #	Ligand	hH1R pKia	hH2R pKib	hH3R pKic	hH4R pKid
1	Histamine	4.6	5.1	8.2	8.1
2	2-(2-Thiazolyl)-ethylamine	5.3			<5
4	Histaprodifen	5.70			<5
6	Diphenhydramine	7.89	5.80	4.60	4.37
8	Mepyramine	8.80	4.63	<5	<5
10	Mizolastine	9.10			<5
11	Levocetirizine	8.15	<6	<6	<4
12	Terfenadine	7.92		<5	<5
13	Fexofenadine	7.54			<5
14	Loratadine	7.21		<5	4.74
15	Desloratadine	8.40	6.45e	<5	5.10
17	4(5)-Methylhistamine	<5	5.10	4.72	7.73
18	Amthamine		6.82		5.30
19	Dimaprit	<5	4.60	6.08	6.42
20	Arpromidine	6.5	6.3-8.0
21	Impromidine	5.2	7.64	6.99	7.76
23	Burimamide	4.3f	5.41	7.36	6.97
24	Cimetidine	4.75	5.84	4.69	5.03
25	Ranitidine	4.47	6.67	4.89	<5
27	Famotidine	<5e	7.56		<5
30	Aminopotentidine	4.60	7.40	7.10	<5
31	Tiotidine	<4	7.77	<4f	<5
32	Nα-Methylhistamine	4.20	4.30	9.00	7.13
33	(R)-α-Methylhistamine	<5	<4	8.6	6.76
34	Imetit	4.30	5.10	9.29	8.48
35	Immepip	4.79	<3.5	9.44	7.79
36	Methimmepip			9.00	5.70
38	Proxyfan			8.2	7.30
40	Thioperamide	3.88	4.27	7.6	7.04
41	Clobenpropit	5.45	5.47	9.0	7.98
42	Ciproxifan	<5	<5	7.1	5.73
45	Pitolisant	5.78	4.96	8.06	<4
48	Conessine	<5	<5	8.3	<5
55	MK-0249	<5	<5	8.2	<5
56	Clozapine	8.65	6.82	<4	6.26
58	JNJ-7777120	<5	<6	5.30	8.09
67	ZPL-389378			6.73	8.31
72	JNJ-39758979	<6	<6	6.0	7.9
74	INCB-38579	<5	<5.3	6.39	8.3
75	ST-1006	<6	<6	6.29	7.9

^aData from Tran et al. (1978); Chang et al. (1979); Kanba and Richelson (1984); De Backer et al. (1993); Leurs et al. (1994a); Vollinga et al. (1994). Sharif et al. (1996); Merlos et al. (1997); Bakker et al. (2001); Gillard et al. (2002a); Esbenshade et al. (2003); Govoni et al. (2003); Thurmond et al. (2004, 2014a,b); Bielory et al. (2005); Xie et al. (2006); Ligneau et al.(2007); Nagase et al. (2008); Zhao et al. (2008); Sander et al. (2009); Rossbach et al. (2011); Appl et al. (2012); Shin et al. (2012); Savall et al. (2014); Where multiple values are reported, they have mostly been averaged.

^bData from Harada et al. (1983); Gantz et al. (1991b); Leurs et al. (1994a, 1995b); Sharif et al. (1996); Kreutner et al. (2000); Saitoh et al. (2002); Esbenshade et al. (2003); Thurmond et al. (2004, 2014a,b); Bielory et al. (2005); Lim et al. (2005); Xie et al. (2006); Preuss et al. (2007); Nagase et al. (2008); Zhao et al. (2008); Sander et al. (2009); Rossbach et al. (2011); Shin et al. (2012); Savall et al. (2014); and Levocetirizine New Drug Application #22-064; Loratadine New Drug Application #21-165. Where multiple values are reported, they have mostly been averaged.

^cData from West et al. (1990); Vollinga et al. (1994); Sharif et al. (1996); Kato et al. (1997); Lovenberg et al. (1999); Ligneau et al. (2000, 2007); Coge et al. (2001b); Liu et al. (2001a); Wieland et al. (2001); O'Reilly et al. (2002); Wellendorph et al. (2002); Wulff et al. (2002); Esbenshade et al. (2003); Thurmond et al. (2004, 2014a,b); Bielory et al. (2005); Lim et al. (2005); Gbahou et al. (2006); Nagase et al. (2008); Zhao et al. (2008);Sander et al. (2009); Mowbray et al. (2011); Rossbach et al. (2011); Appl et al. (2012); Shin et al. (2012); Andaloussi et al. (2013); Savall et al. (2014); and Levocetirizine New Drug Application #22-064. Where multiple values are reported, they have mostly been averaged.

^dData from Ligneau et al., 2000; Liu et al., 2001b; Morse et al., 2001; Zhu et al., 2001; O'Reilly et al., 2002; Esbenshade et al., 2003; Thurmond et al., 2004, 2014a,b; Lim et al., 2005; Gbahou et al., 2006; Ligneau et al., 2007; Nagase et al., 2008; Zhao et al., 2008; Deml et al., 2009; Sander et al., 2009; Mowbray et al., 2011; Rossbach et al., 2011; Appl et al., 2012; Shin et al., 2012; Andaloussi et al., 2013; Savall et al., 2014. Where multiple values are reported, they have mostly been averaged.

^eGuinea pig.

^fRat.