Figure 5.

Effects of H₃-receptor ligands on specific [³⁵S]GTPγ[S] binding to membranes from various rat brain regions. The effects of imetit, a selective agonist, and FUB 465, ciproxifan and thioperamide (10 nM), three inverse agonists, were studied in the absence (open bars) or presence (solid bars) of 1 μM proxyfan. The H₃-receptor density was measured using [¹²⁵I]-iodoproxyfan binding assay (Ligneau et al., 1994) and represented 130±1, 136±6, 108±2, 82±3, 103±4 and 99±6 fmol mg⁻¹ protein in the cerebral cortex, striatum, hypothalamus, thalamus, hippocampus and midbrain respectively. Data are means±s.e.mean of 10–38 determinations from four to six separate experiments. *P<0.05, **P<0.001 vs basal; ⁺P<0.05, ⁺⁺P<0.001 vs without proxyfan.