Mj. Glass et al., ROLE OF CARBOHYDRATE TYPE ON DIET SELECTION IN NEUROPEPTIDE Y-STIMULATED RATS, American journal of physiology. Regulatory, integrative and comparative physiology, 42(6), 1997, pp. 2040-2045
We tested whether carbohydrate source (corn starch, sucrose, Polycose)
influences the choice between a high-fat and high-carbohydrate diet i
n spontaneously feeding rats and in rats stimulated to eat by neuropep
tide Y (NPY) administration or food deprivation. Rats were tested unde
r three diet options: I) a high-fat diet versus a high-corn starch die
t; 2) a high-fat diet versus a high-sucrose diet; and 3) a high-fat di
et versus a high-Polycose diet. During daily and stimulated feeding ra
ts ate more of the high-carbohydrate diet than the fat diet when the s
ource of carbohydrate was sucrose or Polycose; however, when corn star
ch was provided as the carbohydrate source rats ate more of the high-f
at diet. Food-deprived rats increased intake of both the high-fat and
the high-carbohydrate diets, with the proportion of energy ingested fr
om each of the diets resembling that noted during 3 days of spontaneou
s feeding. NPY-injected rats ate more of both the high-fat and high-ca
rbohydrate diets during diet options I and 3, but not during option 2
when the high-sucrose and high-fat diets were offered concurrently. In
that case, rats did not significantly increase their intake of the hi
gh-fat diet. Although carbohydrate source and NPY administration each
influenced diet selection, altering the source of carbohydrate had a m
ore marked effect.