CaR-specific agonist and antagonist stimulate and inhibit gastrin secretion, respectively, in CaR WT mice. (A) Gastrin stimulation by CaR-specific agonist, cinacalcet (100 mg/kg by gavage. **P < 0.01 vs. vehicle (n = 9 mice). (B) Inhibition of gavaged peptone-stimulated gastrin by the CaR-specific antagonist, NP-S2143 (1 mg/kg, i.v., 30 min before gavage) at a dose shown to significantly stimulate PTH secretion compared with vehicle. *P < 0.05 vs. vehicle (n = 9 mice). Results are expressed as the percent change (mean ± SEM) in secretion relative to basal.