ACTIVE IMMUNIZATION AGAINST INSULIN AFFECTS SLEEP AND FEEDING IN RATS

The effects of active immunization against peripheral insulin on different sleep parameters and food consumption were studied in rats. Insulin coupled to thyroglobulin was used as immunogen and rats immunized with thyroglobulin alone served as controls. Active immunization against insulin is summarized as follows: (a) the number of arousals was reduced; (b) waking time decreased by about 20%; (c) slow wave sleep was increased; (d) The amount of sleep increased during the light and dark period; (e) feeding was decreased; (f) body weight was reduced; and (g) the blood glucose level rised. These results are compatible with previous studies showing positive correlation between decrease of insulin secretion, sleep disturbances and decrease of feeding. A possible association between peripheral insulin and brain noradrenergic system, sleep and feeding is suggested.