Figure 6. The effect of endoplasmic reticulum store depletion on the alkalinization-induced calcium rise.

The neurone was pressure injected with fura-2 and held under voltage clamp. Depolarization (20 steps to 0 mV for 100 ms at 5 Hz) or 3 mm TMA application induced a transient rise in calcium. Caffeine, 10 mm, was applied for 10 min. Immediately following caffeine application the size of the TMA-induced calcium rise was reduced. A third application of TMA, after 30 min superfusion in normal Ringer solution, produced a larger calcium rise.