Fig. 6. Inhibitors of signaling via Ca²⁺, ROS, NO, ATP, and IP₃ inhibit γ-H2AX responses in the irradiated and bystander areas.

a Focused 3 × 3 mm beam irradiation experiments and the effect of cytosolic Ca²⁺-chelation with BAPTA-AM, ROS scavenging with NALC, NO scavenging with C-PTIO, purinergic P2X antagonism with PPADS, and IP₃ receptor antagonism with xestospongin C (Xesto C) on γ-H2AX counts (normalized to vehicle) in RBE4 cells in the irradiated zone. An asterisk (*) vs. vehicle (n = 7–10). b Effects in the bystander area. An asterisk (*) vs. vehicle (n = 7–10). c, d Effect in irradiated and bystander areas in pBMECs. An asterisk (*) vs. vehicle (n = 4–7). e BAPTA-AM, NALC, and C-PTIO also inhibited irradiation-induced ATP release (normalized to non-irradiated control). An asterisk (*) vs. vehicle (n = 3–6).