Figure 6. Estimating affinity from efficacy.
If η and E0 are known, EC50 can be
calculated from the maximum response. A. Log-log plot of
EC50 values calculated from
POmax (Eq. 7) versus
EC50 values estimated by fitting CRCs (Eq. 1), with
linear fit (slope=1.08, R2=0.85). red, η=52% agonists
and blue, η=40% agonists (Fig. 4). B. CRCs calculated from
POmax (lines) superimpose
approximately on experimental PO measurements (symbols).