Effects of experience with salty food on salt selection in adrenalectomized rats

Sodium-deficient rats will seek out NaCl in food or solution and regulate their salt need. The question of this study is the extent to which salt-seeking behavior can be modified by long-term exposure to a high NaCl diet. Four female rats were divided into two groups: (1) animals that were fed lab chow with extra NaCl added during breeding, gestation, and until the offspring were weaned, the Experienced group, and (2) animals that ate only plain lab chow until weaning, the Inexperienced group. Food preference was measured in the offspring at age 28-29 and 41-42 days and them about half of each group were adrenalectomized and half sham operated. All animals had access to both plain and NaCl-enriched food and saline for 10 days postoperatively. The saline solution was removed and intake measured for an additional 8 days. Early experience with the high NaCl diet resulted in greater consumption of the NaCl-enriched food preoperatively and altered the pattern of intake following the removal of the saline solution postoperatively. The results indicate that early exposure to a high salt diet can influence the rats' later salt-seeking behavior.