title: Characteristics of insulin-induced hyperphagia in the golden hamster.
abstract: Two experiments were performed to investigate in some detail the behavioural and metabolic effects of the administration of regular insulin to golden hamsters. In Experiment 1 dose-response curves describing the effects of insulin upon both food intake and plasma glucose (PG) were generated. Dosages of less than 20 units/kg did not cause increases in food intake, while dosages of 10 units/kg or greater produced significant hypoglycemia at +6 hr post-injection. There was also a significant inverse linear relationship (r = -.528) between individual hamsters' food intakes and PG levels over the range of insulin dosages. In Experiment 2, insulin (30 units/kg) caused increases in meal frequency but not in meal size, and hyperphagia developed within +3 hr of insulin administration. When food was not available, insulin caused PG levels to fall below control levels at +1 hr and to remain depressed until at least +6 hr post-injection. However when hamsters were allowed to eat, PG did not fall significantly below control levels until +3 hr and began to recover at +5 hr post-injection. Results are discussed in relation to several apparent peculiarities in the hamster's behavioural response to regular insulin, specifically the small magnitude and the slow development of insulin-induced hyperphagia, and the hamster's relative insensitivity to the hyperphagic effect of insulin.
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D006224:Cricetinae / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D004435:Eating / Q000187:drug effects; D005215:Fasting; D005247:Feeding Behavior / Q000187:drug effects; D001068:Feeding and Eating Disorders / Q000503:physiopathology*; D006801:Humans; D006963:Hyperphagia / Q000139:chemically induced / Q000503:physiopathology*; D007328:Insulin / Q000494:pharmacology*; D008297:Male; D008647:Mesocricetus; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D007328:Insulin