Figure 4.

Extracellular Ca²⁺ entry mediates the Ca²⁺ response to NaHS. (A), NaHS (100 μM) failed to elicit intracellular Ca²⁺ levels when the cells were bathed in the absence of extracellular Ca²⁺ (0Ca²⁺), the [Ca²⁺]_i raised following re-addition of extracellular Ca²⁺. (B), mean ± SE of the percentage of mCRC cells presenting a discernible Ca²⁺ release or Ca²⁺ entry in response to 100 μM NaHS. (C), mean ± SE of the amplitude of Ca²⁺ release and Ca²⁺ entry induced by NaHS in mCRC cells. (D), removal of extracellular Ca²⁺ (0Ca²⁺) during the plateau phase caused the [Ca²⁺]_i to undergo a reversible decline to pre-stimulation levels.