In the present study, copper, magnesium, calcium, sodium and potassium homeostasis as well as blood glucose and liver glycogen were investigated in untreated and treated diabetic rats. The ionic alterations in plasma and liver were concomittant with those fluctuations occurring in blood glucose and liver glycogen through all the periods of investigation. In treated rats, insulin injection was able to maintain, for a large extent, the ionic homeostasis. It seems that the endocrine imbalance was responsible for the alterations in both transport and metabolism of those ions. Also, it is possible that alterations in plasma and tissue levels of those ions may  contribute to the development of liver complication.