Ryanodine increases the sensitivity of the α9α10 nAChR for ACh. A Mean and standard error of the percent change in response to 10 μM ACh (at −70 mV, internal BAPTA buffering) for different concentrations of ryanodine (30, 60, 100, and 200 μM, n = 3–9 per concentration). B Concentration-response curves to ACh in the absence and presence of 200 μM ryanodine (n = 3–7 per concentration). Ryanodine increased the apparent affinity of the recombinant α9α10 nAChR for ACh and also the amplitude of responses to saturating concentrations of this agonist. Vhold = −70 mV.