Influence of reversible obesity on eating behavior, blood glucose, and insulin in the rat
Steffens, A.B.
American Journal of Physiology 228(6): 1738-1744
1975
ISSN/ISBN: 0002-9513 PMID: 1155607 Document Number: 89598
Excess food intake, resulting in obesity, was induced in rats by electrical stimulation, 3 sessions of 30 min/day for 3 weeks, of the lateral hypothalamus (LH). Except during the stimulation sessions, no voluntary food intake occurred. In the subsequent recovery period, accurate records of spontaneous feeding were made. Glucose, insulin and free fatty acids in blood were estimated during the stimulation and the recovery periods. During feeding elicited by stimulation in the obese phase, there was a large rise in glucose. Insulin, which was high in the intervals between stimulation sessions, showed no change, a small decline or a large fall, respectively, during stimulation in the morning, afternoon or night. When food was withheld during stimulation, glucose rose and insulin fell. After termination of stimulation the first spontaneous meal was begun a mean 28 h 15 min later, when the glucose and insulin values had returned to normal. Insulin response to the first spontaneous meal was exaggerated. In the next 10 days a rapid fall in bodyweight occurred and food intake was at a minimum; insulin was high and glucose was below normal and they became normal again only after recovery of normal bodyweight and food intake. It is tentatively concluded the regulation of body energy stores (bodyweight) is achieved through the control of food intake by circulating insulin and glucose values.