Erythrocyte insulin binding abnormalities in fibrocalculous pancreatic diabetes

Abstract

Insulin binding to erythrocyte insulin receptors was studied in 17 patients (13 men and 4 women) with fibrocalculous pancreatic diabetes mellitus (FCPD) and compared with that of 14 newly diagnosed NIDDM patients matched for age, sex and severity of hyperglycemia, and 14 age and sex-matched non-diabetic control subjects. In the uncompensated diabetic state, mean (±S.D.) specific binding of insulin was lower in both FCPD and NIDDM patients, compared with non-diabetic controls (P < 0.001). Control of diabetes with short term therapy (2-6 weeks) resulted in a significant improvement in the mean specific insulin binding in both FCPD and NIDDM patients (P < 0.001) due to increased binding affinity in the former, and increased affinity and the number of binding sites in the latter. As compared to short term therapy, chronic therapy (5-8 months) in FCPD patients resulted in a marginal decrease in specific insulin binding. However, this was still significantly higher than the basal value (P < 0.05). FCPD patients had an initial low mean basal plasma IRI and a much lower mean stimulated IRI response as compared to NIDDM and non-diabetic controls.