Figure 2. Ca²⁺ response to S1P, histamine and BHQ in the absence of external Ca²⁺ and the effect of SK&F96365 in HUVECs.

After external Ca²⁺ was removed (0 Ca²⁺, no EGTA), 3 μm histamine (A), 10 μm BHQ (A) or 0.3 μm S1P (B) was applied; subsequently 2.2 mm Ca²⁺ was added to the bathing solution in the presence of each agonist. C, in the presence of 0.3 μm S1P, external Ca²⁺ was removed for the duration indicated by the bar; subsequently, 10 μm SK&F96365 was applied. The line shows the change in [Ca²⁺]_i obtained from a representative cell. The averaged responses were from 10 separate cells.