CASR and chronic kidney disease: We first characterized the effects of Pi on CaSR-mediated signaling, demonstrating that raising Pi concentration from 0.8 (physiological) to 2 mM (CKD-like) significantly inhibited maximal levels of \documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$${\mathrm{Ca}}_i^{2 + }$$\end{document}Cai2+-mobilization by 45% and pERK by 30%.