Regulation of the number of insulin receptors in human fat cells.

Previous studies have shown that the ambient insulin concentration can regulate the number of insulin receptors. The concept implies that hyperinsulinemia may cause a reduced receptor number and cellular insulin resistance. The possible importance of this concept on the mode of treatment of diabetics was studied. Five insulin-dependent diabetics were studied under metabolic ward conditions while treated with one dose of long-acting insulin or with smaller amounts of short-acting insulin 30 min before meals. Adipose tissue samples were taken on each regime. The number of insulin receptors were increased in all subjects on the short-acting regime and this was coupled with an increased insulin sensitivity in the adipocytes. One probable reason for this finding is that the insulin levels were higher during the long-acting regime leading to an attenuated number of insulin receptors. The data show that short-acting insulin taken repeatedly in connection with meals leads to a more normal state and an increased peripheral insulin sensitivity as compared to a regime of one dose of long-acting insulin.