Fig. 3

Pathophysiologic Pi concentrations increase PTH secretion in human parathyroid cells. Effect of hyperphosphatemia on PTH secretion (measured every 2 min) from perifused, freshly isolated human parathyroid cells (upper). One millimolar Ca²⁺ was used as an internal control to confirm \({\mathrm{Ca}}_o^{2 + }\) responsiveness and CaSR expression in the cell preparation. Data normalized to baseline (initial exposure to 1.2 mM \({\mathrm{Ca}}_o^{2 + }\)/0.8 mM Pi) and shown in box-and-whisker plots. Data from N = 9 human samples from nine biologically independent patients; individual traces are shown in Supplementary Fig. 4. ns not significant, ^***P < 0.001, ^****P < 0.0001 by Friedman’s with Dunn’s post hoc test. Source data are provided as a Source Data file