Relations Between Self-Selected Intake of Nutrients and Body Fat Accumulation in Rats Fed Ad Libitum or for 8-hours a Day

흰쥐에게 식이를 무제한 공급 또는 공급시간을 제한하였을 때 영양소의 선택적 섭취행동과 체지방 축적과의 관계

This study was aimed to investigate the relations between self-selected intake of 3 macronutrie-nts and body weight gain and body fat accumulation in male rats given three isocaloric diets differing carbohydrate protein and fat contents concurrently. Also the effect of dietary restriction was observed. Forty two male rats of Sprague-Dawley strain weighing 68.7$\pm$6.1g were randomly divided into 2 groups and were allowed to have foods from 3 different cups for 8-hours a day or ad libitum, After 12 weeksthey were decapitated and their brains were quickly removed and frozen until they were assayed for serotonin and its metabolite 5-HIAA The carcass was dried at 105$\pm$2$^{\circ}C$ and measured the contents of body water and body fat. The animals chose a moderately high and constant carbohydrate level and showed the increase of percent protein intake with age and great individual variations. Protein in the diet seemed to trigger appetite and increase food intake which resulted in higher weight gains and in more fat deposition in the body. The concentration of brain serotonin did not show any correlations with the intake of nutrients. the accumulation of body fat and the gain of body weight.