TABLE 1

Binding parameters of orthosteric ligands and allosteric modulators

Ki, KB, and α values are shown with corresponding 95% confidence intervals in parentheses. For the first row, [3H]CP55940 and for the second row [3H]SR141716A are used as the orthosteric tracers. Three independent experiments, each done in duplicate, were used in each case.

CP55940SR141716ALDK1285LDK1288LDK1305PSNCBAM1
KiKiKBαKBαKBαKBα
[3H]CP55940nMnMnM11.5nM5.3nM4.3nM2.7
1.24ND19862.520.041.4
(0.62–2.48)(141–277)(7.7–17.2)(41.6–94.1)(3.9–7.2)(13.5–29.5)(3.4–5.6)(18.8–91.1)(2.1–3.5)
[3H]SR141716AND2.134730.12240.11150.31560.1
(1.37–3.32)(160–1350)(0.0–0.3)(64.4–722)(0.0–0.3)(29.9–454)(0.1–0.4)(14.2–983)(0.0–0.4)
  • Ki, equilibrium dissociation constant of orthosteric ligand; KB, equilibrium dissociation constant of allosteric modulator; α, cooperativity factor between orthosteric and allosteric ligand binding; ND, not done.