Figure 4.

Effects of anaphylatoxins on Akt and L-type Ca²⁺ channel phosphorylation in ARPE-19 cells. (A) Akt phosphorylation at serine in position 473 was examined in ARPE-19 cells treated with C3a, C5a, or the combination of C3a/C5a at 1, 5, 10, and 15 min and compared to unstimulated (designated as 0 min) cells. Akt phosphorylation levels were normalized to β-actin (relative p-Akt levels), and slopes of the time course were determined. (B) L-type Ca²⁺ channel (Ca_V1.3 subunit) phosphorylation was examined at the 15-min time point after immunoprecipitation with anti-Ca_V1.3 and blotting for phosphor-tyrosine. Ca_V1.3 phosphorylation levels were normalized to β-actin (relative Ca_V1.3 levels). Anaphylatoxins were applied at concentrations of 300 nM (C3a) and 50 nM (C5a). Data are mean + SEM, n = 3, *p < 0.05, **p < 0.01 (Student’s t-test).