Nicotine's effects on female rats' body weight: caloric intake and physical activity.

Caloric intake and physical activity contribute to the inverse relationship between nicotine and body weight in male rats. In contrast, the relative contribution of these behavioral variables to the nicotine/body weight relationship in female rats has has not been investigated. Recent research indicates that males and females respond differently to nicotine. The present study was designed to determine the role of physical activity and food consumption in body weight changes associated with nicotine administration in female rats. Nicotine or saline was administered chronically to 24 female rats for 19 days. Body weight, food consumption, water consumption, and physical activity were measured before, during, and after nicotine administration. Body weight and food consumption decreased during and increased after nicotine administration. However, there were no changes in physical activity that could account for these changes in body weight. These results corroborate the report that males and females respond differently to nicotine.