Amylin infusion reduces food intake and slows
body weight gain in rodents. In obese male rats,
amylin (but not pair feeding) caused a preferential reduction of fat mass with
protein preservation despite equal
body weight loss in
amylin-treated (fed ad libitum) and pair-fed rats. In the present study, the effect of prior or concurrent food restriction on the ability of
amylin to cause
weight loss was evaluated. Retired female breeder rats were maintained on a high-fat diet (40% fat) for 9 wk. Prior to
drug treatment, rats were either fed ad libitum or food restricted for 10 days to lose 5% of their starting
body weight. They were then subdivided into treatment groups that received either vehicle or
amylin (100 microgxkg(-1)xday(-1) via subcutaneous minipump) and placed under either a restricted or ad libitum feeding schedule (for a total of 8 treatment arms).
Amylin 1) significantly reduced
body weight compared with vehicle under all treatment conditions, except in always restricted animals, 2) significantly decreased percent body fat in all groups, and 3) preserved lean mass in all groups. These results indicate that
amylin's anorexigenic and fat-specific
weight loss properties can be extended to a variety of nutritive states in female rats.