TABLE 1

[³H]Almorexant and [³H]Cp-1 binding properties at hOX₁ and hOX₂ and [³H]SB-674042 binding at hOX₁

Saturation binding isotherms of [³H]almorexant, [³H]Cp-1, and [³H]SB-674042 were performed on membrane preparations from HEK293 cells transiently transfected with hOX₁ or hOX₂ as described under Materials and Methods. The K_d and B_max values are mean ± S.E., calculated from three independent experiments (each performed in triplicate).

Radioligand and Receptor	K_d	B_max
	nM	pmol / mg protein
[³H]Almorexant (37°C)
hOX₁	1.3 ± 0.1	27.2 ± 0.6
hOX₂	0.17 ± 0.01	15.72 ± 0.2
[³H]Cp-1 (37°C)
hOX₁	17.52 ± 1.3	29.83 ± 0.7
hOX₂	0.40 ± 0.04	18.64 ± 0.5
[³H]SB-674042 (23°C)
hOX₁	0.74 ± 0.07	13.76 ± 0.38