STABILITY OF PREFERENCE FOR SALINE IN RATS OVER DAYS

Stability of preference for 0.5% and 2.0% concentrations of saline, separately paired with water, was assessed in rats. Over a 6-day test period, intake of hypotonic (0.5%) saline was found to decrease while that of water increased concomitantly. Over a second 6-day test period, intake of hypertonic (2.0%) saline decreased slightly while water intake increased slightly. A 9-day respite from saline did not alter the original pattern of water and saline intake in a subsequent retest. Possible explanations for changes in preference for saline over time are discussed in terms of changes in salivary sodium and taste receptors, increased water need, and alterations of the central nervous system evaluation of the gustatory input. © 1969, Psychonomic Journals, Inc.. All rights reserved.