Increased monoamine oxidase activity and imidazoline binding sites in insulin-resistant adipocytes from obese Zucker rats

Figure 8 Influence of tyramine on idazoxan binding to liver crude membranes. Total and non-specific binding of ³H-idazoxan to liver crude membranes from lean Zucker rats is shown without (open symbols) and with 5 mmol/L tyramine (closed symbols) added prior to 45-min incubation at room temperature. Without tyramine, the resulting specific binding was characterized by a B_max of 622 ± 15 fmol/mg protein and a K_D of 5.1 ± 0.4 nmol/L. Each point is the mean ± SEM of three liver preparations containing 617 ± 120 µg protein/assay. Inhibitory influence of tyramine on total binding was significant at P < 0.001.