Figure 4.

Averaged concentration-effect curves of muscarinic agonists for I_cat activation. The curves were obtained from experiments as described in Figure 3. The data points for each agonist were fitted with a logistic function. The curves, depending on whether significantly different from carbachol's curve in the maximum response, are classified into the two groups; (a), not significant and (b), significant (P<0.05). The dotted curve in (b) is for carbachol. Each point indicates the mean±s.e.mean of measurements in 5 – 14 cells.