Figure 7.

Ivermectin potentiates [Ca²⁺]_i signals but not Yo-Pro-1 entry in HEK_hP2X7 cells. (A) Fluo-4-loaded HEK_hP2X7 cell suspensions were subjected to fluorimetric [Ca²⁺]_i analysis in a fluorescence plate imager. Cell suspensions were pretreated for 5 min with the indicated modulators, their maximal solvent concentration (0.1% DMSO) or buffer as indicated, and stimulated with 1 mM ATP. Background-corrected signal F values were normalized to their respective initial intensities F₀. (B) Experiments with various ivermectin concentrations were performed as shown in panel A. Means ± SEM of 36 dilution series measured in five independent experiments are shown. Note the discontinuous scale of the axes. *P < 0.05; **P < 0.01, significantly different from corresponding solvent controls. (C) HEK_hP2X7 cell suspensions were re-suspended in HBS, containing 0.1 mM CaCl₂ and no MgCl₂ (low-DIC HBS), and 2 µM Yo-Pro-1. The indicated modulators were added 5 min prior to the measurement. Fluorescence signals were recorded in a plate reader before and after injection of 1 mM ATP (final concentration). (D) Statistical analysis of experiments performed as shown in panel C. Means and SE of n= 4–6 independent experiments performed in duplicates are shown.