The effect of glucose on the food intake of goldthioglucose injected mice.

Abstract

has postulated the presence of glucoreceptors located primarily in the ventromedial hypothalamic nuclei of the brain which a:re activated by glucose in the measure that they utilize it.. According to Mayert hunger occurs when glucose is not available for metabolic purposes and satiation supervenes when glucose is made available.Control of this mechanism rests with the glucorecepto~s. These receptors are believed to be destroyed when an injection .of the compound goldthioglucose is given to mice. These anlmals subsequently become obese and are found to have gold deposits and lesions in the ventromedial area and also in other parts of the brain.If the glucoreceptors are dest:r;oyed and cannot respond to the presence of glucose in the blood, it would be predicted that food intake would not change with the glucose level. The purpose of this investigation was to see if the food intake of goldthioglucose injected animals is affected by a glucose injection. 0One hundred and twenty mice were divided into four groups. One group, the controls, received no goldthioglucose. The other three groups received the following dosages: .5 mg. of goldthioglucose per gram of body weight, 1.0 mg. of goldthioglucose per gram of body weight and 1.3 mg. of goldthioglucose per gram of b~dy weight. Fifty seven days after the goldthioglucose injection a training period began in which the mice were taught to consume their entire daily food intake during a 50 .minute period. Then the experimental period began during which the animals were maintained on the 23 hour and 10 minute deprivation schedule. During this period the mice were given intra·peritoneal injections of 60 mg. of glucose or normal saline on alternate days for ten days. The amount of food consumed in the 50 minutes beginning 15 minutes after the glucose or saline injection was determined.Food intake of the goldthioglucose injected animals was not different tr~n that of the controls under any factor of the experiment.The results do n·ot .support :Hayer's idea that the glucoreceptors as he describes them are destroyed by goldthioglucose. .Analysis of Variance Summary Table • Mean Food Intake in Grams Based Upon the LevelHunger and feeding are under the control of many sensor3 factors, both learned and unlearned. These contribute in an ad.di tive way to the arousal of hunger and to the development of satiation: Taste, smell, gastric contractions and gastr~c distension~ to name some major ones.Added to these are powerful influences from the more interr1al enviro~~ent, including both osmotic and specific chemical changes~ It is the understanding of these internal physiological determinents of feeding behavior, and more specifically the influence of blood ~glucose on hunger and satiety which is of concern here. contractions the basis of a complete theory concerning the regulation of appetite. This theory was based on the idea that the control of food intake rests with the periphery of the body rather than with the central nervous system. With these efio~ts to explain empirically t...