Figure 2.

Inhibition of the binding of [³H]-NMS to the M₁–M₄ subtypes of muscarinic receptors by α-truxillic acid bis-4-piperidylbutyl ester (compound III, top panel), its quaternary bis-N-methyl derivative (compound VI, middle panel) and bis-N-ethyl derivative (compound VII, bottom panel). Abscissa: log of the concentration of the ester. Ordinate: [³H]-NMS binding in the presence of the ester, expressed as per cent of the binding in the absence of the ester. Data are means±s.e.mean of at least two experiments with incubations performed in triplicates.