Fig. 6.

Persistent inflammatory injury does not alter the number or affinity of α4β2 nicotinic cholinergic receptors in the rostral ventromedial medulla. Saturation isotherms for binding of [³H]epibatidine to membrane homogenates of the rostral ventromedial medulla of rats 4 h after intraplantar injection of saline (☐) or CFA (∘) in the hind paw. Symbols represent the mean ± SEM. of triplicate samples. Results from a single representative experiment are illustrated. Specific binding was determined by subtracting nonspecific binding from total binding at each of these concentrations. Specific binding data were fitted using nonlinear regression in GraphPad Prism. Inset, Magnified view of curves at low radioligand concentrations.