Effect of fasting and dexamethasone on binding characteristics of canine erythrocyte insulin receptors

Insulin binding characteristics of canine erythrocyte insulin receptors were studied before and after a 72-hour fast, and one and three days following glucocorticoid (dexamethasone) administration. The 72-hour fast tended to increase maximum insulin binding, but no significant differences were found. The administration of dexamethasone resulted in an increased maximum binding of insulin to its receptors which, at day 1, was due to an increase in receptor concentration, and at day 3, to an increased insulin binding affinity of the receptor. These data suggest that the erythrocyte insulin receptor may be useful in clinical and experimental studies in the dog.