Figure 6.
Extracellular pH modulates CaR-induced suppression of PTH secretion. (A) Human parathyroid cells were perifused in 1.2 mM calcium-containing buffers at pHo 7.0–7.8 (at 5-minute intervals) and PTH secretion quantified as fg per minute per cell. See Supplemental Material for the complete methods. (B) Quantification of these changes is shown as percentage control. n=3 independent experiments. *P<0.05 by unpaired t test (one-tail) on PTH values following preliminary experiments investigating the effect of 0.4-unit pHo changes on both human and bovine parathyroid cells (not shown).