Figure 4.

Inhibition of [³⁵S]GTPγ[S] binding to membranes of CHO(WT) and CHO(hH₃R) cells by GTPγS. Membranes of CHO(WT) or CHO(hH₃R) cells expressing ∼300 fmol mg⁻¹ protein, were incubated with 0.1 nM [³⁵S]GTPγ[S] and increasing concentrations of GTPγS, in the presence, when required, of 1 μM imetit or ciproxifan. The inset shows the same data after subtraction of [³⁵S]GTPγ[S] binding to membranes of CHO(WT) cells. Means±s.e.mean of 23–25 determinations from two independent experiments. *P<0.01; **P<0.001 vs CHO(WT) cells; ⁺P<0.05; ⁺⁺P<0.01; ⁺⁺⁺P<0.001 vs CHO(hH₃R) cells in the absence of ligand.