Fig. 6.

Ryanodine clamped nerve-evoked Δ[Ca²⁺]_i near the threshold level of [Ca²⁺]_i for LHRH release. Superimposed [Ca²⁺]_i traces were responses evoked by 50, 100, 150, 200, 300, 600, and 1000 stimuli. All stimuli were delivered at 20 Hz. The 0 [Ca²⁺]_i level is indicated by the line at the bottom of each panel. Thedotted vertical lines in A and Bindicate the time when later stimuli no longer produced net increase in [Ca²⁺]_i. Note that this time corresponded to the 460th stimulus in NR and the 200th stimulus in RY.