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Fluctuation of Insulin Resistance in a Leprechaun With a Primary Defect in Insulin Binding*

1988; Oxford University Press; Volume: 66; Issue: 5 Linguagem: Inglês

10.1210/jcem-66-5-1084

1945-7197

Masashi Kobayashi, Yasumitsu Takata, Toshiyasu Sasaoka, Yukio Shigeta, Katsumi Goji,

Metabolism, Diabetes, and Cancer

A 3-month-old female leprechaun demonstrated extreme insulin resistance with hyperinsulinemia (330 μmol/L) and resistance to exogenous insulin. Insulin binding to erythrocytes, cultured lymphocytes, and fibroblasts from the patient were decreased to less than 20% of normal, whereas insulin-like growth factor I binding to fibroblasts was normal. Antiinsulin receptor antibody binding to cultured lymphocytes was also decreased to 20% of normal, indicating a decreased concentration of insulin receptors on the cell surface. The ability of insulin to stimulate d-[14C]glucose uptake was decreased to 35% of normal in the patient' s fibroblasts, and the dose-response curve was shifted to the right. With time, the insulin resistance fluctuated from near normal (fasting insulin, 244.0 pmol/L) to severe resistance (fasting insulin, 5740–9328 pmol/L), and an insulin tolerance test revealed amelioration of insulin resistance during remission. However, insulin binding to erythrocytes and adipocytes was decreased persistently to 20% of normal. These results indicate that the patient had a primary defect in her insulin receptors, i.e. decreased insulin receptor concentration. The variable degree of insulin resistance was possibly due to variable receptor function in the signal transmission process.