Fig. 7.

Muscarinic agonist stimulated phosphoinositide hydrolysis in CHO cells expressing the human M₃ muscarinic receptor. a and b, concentration-response curves of various muscarinic agonists. c, corresponding estimates of log RA_i, log RI_i, and their ratio, log RA_i/log RI_i. The data in a and b are from Ehlert et al. (1999) and represent the mean increase in [³H]inositol phosphates, expressed relative to basal accumulation in the absence of agonist. Mean values ± S.E.M. from four experiments are shown.