Table 1. Log K_D values obtained from ³H-CGP 12177 whole cell binding studies at the three turkey β-adrenoceptors.

	tβtrunc		tβ3C		tβ4C		Human β1	Human β2	Human β3
Acebutolol	−5.85±0.02	6	−5.39±0.09	10	−5.41±0.08	6	−6.46	−6.08	−4.41
Adrenaline	−6.01±0.04	6	−5.81±0.06	9	−5.77±0.08	7	−5.15	−6.13	−4.70
Alprenolol	−7.96±0.04	5	−8.44±0.10	7	−7.85±0.10	7	−7.83	−9.04	−6.93
Atenolol	−5.40±0.06	6	−4.75±0.10	10	−4.76±0.05	7	−6.66	−5.99	−4.11
Betaxalol	−6.90±0.04	6	−6.29±0.08	8	−6.24±0.06	7	−8.21	−7.38	−5.97
BRL35135A	−6.32±0.07	5	−7.42±0.06	5	−6.39±0.03	5	−6.08	−7.38	−6.73
BRL37344	−5.19±0.03	6	−6.28±0.06	7	−5.89±0.10	7	−5.19	−6.51	−6.45
Bisoprolol	−6.70±0.03	6	−5.58±0.08	6	−6.26±0.08	7	−7.83	−6.70	−5.67
Bupranolol	−8.43±0.04	6	−9.07±0.07	7	−8.18±0.09	7	−8.51	−9.85	−7.04
Bucindolol	−9.43±0.06	7	−9.72±0.09	9	−9.41±0.07	6	−9.31	−9.99	−8.04
Butoxamine	−5.24±0.03	6	−5.99±0.08	6	−4.90±0.05	4	−4.85	−6.23	>−4
Carazolol	−10.20±0.05	6	−10.92±0.11	6	−10.27±0.09	6	−9.69	−10.49	−8.35
Carvedilol	−9.43±0.05	5	−9.58±0.07	7	−9.91±0.02	7	−8.75	−9.40	−8.30
CGP20712A	−7.53±0.04	8	−5.40±0.11	9	−6.05±0.07	12	−8.81	−6.11	−5.19
Cimaterol	−7.17±0.03	9	−7.06±0.08	8	−6.75±0.04	8	−6.57	−7.26	−5.28
CL316243	>−4	6	>−4	4	>−4	4	>−3	−4.10	−5.11
Clenbuterol	−6.74±0.07	6	−7.38±0.10	7	−6.44±0.03	7	−6.62	−7.90	−5.35
S-Cyanopindolol	−10.89±0.06	6	−11.37±0.07	6	−10.81±0.09	6	−10.39	−11.09	−8.36
Denopamine	−6.29±0.05	7	−5.63±0.06	6	−5.95±0.03	6	−6.12	−5.83	−5.30
Dobutamine	−5.69±0.03	6	−5.57±0.06	8	−6.00±0.06	7	−5.23	−5.84	−5.09
Fenoterol	−6.36±0.03	6	−6.69±0.07	10	−6.22±0.10	10	−5.04	−7.03	−5.39
Formoterol	−7.33±0.06	6	−7.96±0.07	7	−7.70±0.07	7	−6.11	−8.63	−5.82
ICI118551	−7.20±0.03	5	−8.93±0.06	9	−7.37±0.03	9	−6.52	−9.26	−6.44
ICI215001	−5.79±0.05	6	−5.31±0.09	7	−6.55±0.06	10	−6.37	−5.86	−6.63
Isoprenaline	−6.86±0.08	7	−6.50±0.08	7	−6.71±0.09	7	−6.06	−6.64	−5.52
Labetolol	−7.51±0.05	6	−7.42±0.04	7	−7.70±0.04	6	−7.63	−8.03	−6.18
L755507	−7.17±0.03	7	−6.56±0.06	5	−7.63±0.11	5	−6.23	−6.83	−8.60*
Metaproterenol	−5.64±0.07	6	−5.38±0.09	5	−5.13±0.09	6	−4.71	−5.30	−4.06
Metoprolol	−6.42±0.03	7	−5.96±0.09	6	−5.78±0.07	7	−7.26	−6.89	−5.16
Nadolol	−7.99±0.04	6	−7.95±0.09	6	−7.74±0.03	6	−7.23	−8.60	−6.18
Noradrenaline	−6.60±0.03	6	−4.94±0.07	7	−6.30±0.08	7	−5.74	−5.41	−5.53
Nebivolol	−8.25±0.05	6	−7.78±0.09	8	−8.83±0.08	9	−9.06	−7.92	−7.04
Pindolol	−8.55±0.03	6	−8.71±0.10	8	−8.28±0.06	7	−8.57	−9.23	−7.08
Pronethalol	−6.85±0.01	6	−6.99±0.07	7	−7.06±0.04	7	−6.44	−7.36	−5.89
Propranolol	−8.51±0.05	7	−8.49±0.06	7	−8.51±0.06	7	−8.16	−9.08	−6.93
Ractopamine	−6.75±0.03	6	−6.65±0.04	6	−6.57±0.04	6	−6.97	−6.93	−5.82
Salbutamol	−4.99±0.03	6	−6.14±0.07	7	−5.36±0.05	7	−4.66	−6.12	−4.33
Salmeterol	−5.92±0.04	8	−8.50±0.07	8	−7.09±0.04	8	−5.73	−9.26	−6.33
SDZ21009	−9.27±0.08	6	−10.17±0.08	10	−9.06±0.07	7	−8.94	−10.28	−7.10
SR59230A	−7.39±0.04	7	−7.96±0.08	6	−7.65±0.06	7	−7.54	−8.45	−7.37
Sotalol	−6.14±0.06	6	−6.27±0.08	6	−6.16±0.05	7	−5.77	−6.85	−5.05
Terbutaline	−4.61±0.04	6	−5.62±0.09	10	−4.47±0.05	5	−3.82	−5.62	−3.90
Timolol	−8.76±0.02	5	−9.24±0.10	11	−8.70±0.06	7	−8.27	−9.68	−6.80
Tulobuterol	−5.60±0.06	7	−6.64±0.08	9	−5.46±0.04	7	−5.62	−6.83	−4.72
Xamoterol	−6.58±0.02	6	−5.64±0.09	8	−6.23±0.05	7	−7.22	−6.07	−4.45
ZD2079	−3.77±0.03	4	>−4	4	>−4	4	−4.21	>−4	−4.59
ZD7114	−7.30±0.09	6	−6.59±0.10	7	−7.59±0.04	7	−7.58	−7.31	−6.78
zinterol	−6.40±0.03	6	−7.62±0.08	6	−6.80±0.03	6	−5.96	−8.04	−6.27

Log K_D values obtained from ³H-CGP 12177 whole cell binding studies in CHO cells stably expressing either the tβtrunc, tβ3C or tβ4C adrenoceptors. The human β1 β2 and β3-data is taken from [25] and [30] and is given for comparison. Values represent mean ± s.e.m. for n separate experiments.

*binding to site 1 [30].