Chemosensation of calcium

AGFD 207

Michael G. Tordoff, tordoff@monell.org, Monell Chemical Senses Center, 3500 Market St, Philadelphia, PA 19104
Calcium is essential for survival and good health. Low calcium intakes of humans have been implicated in several chronic diseases including osteoporosis, obesity and hypertension. Many animals have a specific calcium appetite, which implies they can detect the mineral and consume sufficient of it to meet their needs. To determine how they do this, we have exploited inbred strains of mice that differ in their avidity for calcium. A genome scan and studies with congenic and knockout mice revealed that calcium consumption is under the control of two receptors, the so-called “sweet taste” receptor, T1R3, and the calcium-sensing receptor, CaSR. Our results reveal a mechanism by which calcium is detected in the oral cavity. The existence of an oral calcium detector raises the possibility that calcium should be considered a specific taste.