Calcium deprivation increases the palatability of calcium solutions in rats

Calcium-deprived rats have elevated intakes of CaCl 2, other calcium salts, and some non-calcium compounds. We used taste reactivity to examine the effects of calcium deprivation on the palatability of CaCl 2 and other solutions. Nine male Sprague–Dawley rats were calcium-deprived by maintenance on a low-calcium diet, and eight replete rats were used as controls. All rats were videotaped during intraoral infusion of the following solutions: 30 and 300 mM CaCl 2, 30 mM calcium lactate, 100 and 600 mM NaCl, 30 mM MgCl 2, 1 mM quinine·HCl, 2.5 mM sodium saccharin, and deionized water. We counted individual orofacial and somatic movements elicited by the infusions and used them to calculate total ingestive and aversive scores. Relative to controls, calcium-deprived rats gave a significantly larger number of tongue protrusions and had higher total ingestive scores for CaCl 2, calcium lactate, NaCl, and MgCl 2. Our results suggest that CaCl 2, calcium lactate, NaCl, and MgCl 2 taste more palatable to rats when they are calcium-deprived than replete, and this may be responsible for the increased intake of these solutions following calcium deprivation.