Increased Gastrin and Calcitonin Secretion after Oral Calcium or Peptones Administration in Patients with Hypercalciuria: A Clue to an Alteration in Calcium-Sensing Receptor Activity

The calcium-sensing receptor (CaSR) has been detected in human antral gastrin-secreting cells, where, upon calcium and/or amino acid allosteric activation, it stimulates gastrin secretion. Patients with absorptive hypercalciuria (AH) display an enhanced gastric acid output; therefore, we evaluated the secretion of gastrin in subjects with AH ( 30 subjects vs. 30 healthy female controls, all postmenopausal) after oral calcium administration ( 1 g calcium gluconate) and, on a separate occasion, after peptone loading test ( protein hydrolyzed, 10 g). Gastrin and monomeric calcitonin responses were higher in AH after both oral calcium administration ( P < 0.01) and peptone loading ( P< 0.01). B…