Fig. 7.

A: typical experiment showing the lack of effect of carbachol in the presence of ryanodine (30 μM). Summary of the effect of ryanodine on 8 cells. B: 2 repeatable responses to carbachol before treatment with ryanodine in the absence of external Ca²⁺. Subsequent application of ionomycin was able to cause an increase in intracellular Ca²⁺. C: carbachol-induced Ca²⁺ transient in normal solution and then repeated in external Ca²⁺-free solution. Application of tetracaine (100 μM) abolished the carbachol response. D: summary of the effect of tetracaine in 7 cells. *Statistical significance.