Figure 6. [Ca²⁺]_i in RSC loaded with fura-2.

A, removal of Ca²⁺ from the bath solution by EGTA induced a decrease in [Ca²⁺]_i by 75 nm, which was reversible upon washout of EGTA. B, an increase of [Ca²⁺] in the bath from 1 to 20 mM increased [Ca²⁺]_i by 137 nm; LCRK (0.3 μm) was without affect on [Ca²⁺]_i. C, double stimulation of the preparation with angiotensin II (ANG II) increased [Ca²⁺]_i by 64 and 69 nm. Application of LCRK (0.3 μm) prior to and during the second challenge did not modify the response. D, superfusion of 60 mM K⁺ increased [Ca²⁺]_i by 43 and 40 nm.