Fig. 6

Fluorometric kinetic measurements of [Ca²⁺]_i in EA.hy926 and HMEC-1 cells. A Summary bar graph showing the average maximum increase in the F₃₄₀/F₃₈₀ ratio in HMEC-1 and EA.hy926 cells labeled with Fura-2-AM and exposed to flow of buffer (DPBS), ionomycin, thapsigargin, ATP, bradykinin, acetylcholine and angiotensin II. Changes in the F₃₄₀/F₃₈₀ ratio induced by DPBS were subtracted in all subsequent measurements to obtain ligand-specific responses. Bars display AM of maximum amplitude in F₃₄₀/F₃₈₀ ratio ± SE (n ≥ 8). Statistical significance was determined using a nonparametric t-test (Mann-Whitney). A P value of < 0.05 was considered to be statistically significant (*P < 0.05 between EA.hy926 and HMEC-1 cells). Time course of the changes in the F₃₄₀/F₃₈₀ ratio during the injection of B) buffer (DPBS), C) ionomycin (10 μM), D) thapsigargin (1 μM), E) ATP (100 μM), F) bradykinin (10 μM), G) acetylcholine (300 μM) and H) angiotensin II (10 μM) in EA.hy926 and HMEC-1 cells loaded with the Ca²⁺-sensitive fluorescent dye Fura-2-AM. Data are presented as AM ± SEM (n ≥ 9)