Effects of exercise and anion on intake of sodium solutions in Syrian hamsters

Previous studies have shown that hamsters have low spontaneous intakes of NaCl solutions and are refractory to induction of salt appetite. In order to examine the generality of these results, the intakes of NaCl and NaHCO3 solutions are reported for hamsters housed either in normal laboratory conditions (sedentary) or with free access to exercise wheels. Spontaneous salt intakes, as well as those induced by acute sodium depletion and treatment with either the angiotensin converting enzyme inhibitor, enalapril, or deoxycorticosterone acetate (DOCA), were measured. The intakes of NaCl and NaHCO3 were similar. Salt intakes tended to be lower in exercising than in sedentary groups. Neither acute sodium depletion nor administration of enalapril increased salt intake systematically, but treatment with DOCA increased intakes of both salt and water. These results are contrasted with the efficacy of all three treatments to induce salt appetite in rats.