402 GROWTH HORMONE EFFECTS ON ERYTHROCYTE INSULIN BINDING

Abstract

Growth hormone (GH) deficiency is associated with increased body fat, increased insulin sensitivity, and relative insulinopenia, suggesting possible interaction of GH and insulin receptor binding (IRB). We have measured erythrocyte IRB in 15 growth hormone deficient (GHD) children, ages 2-13 years, before treatment, after short-term high-dose GH (2 mg bid × 7 days), and long-term maintenance GH therapy (2 mg tiw × 2-12 mos). IRB was measured after fasting (16 hrs) and feeding (4 hrs). Fasting IRB in GHD patients, control children, and adults were 8.2±2.4, 7.4±2.4, and 8.2±2.3%, respectively. Corresponding concentrations of serum glucose were 78, 88, 82 mg/dl, those of insulin 12.2±3.4, 17.3±3.4, 11.2±2.8 uU/ml. There was no significant change in IRB in GHD with feeding vs fasting or short-term high-dose (7.3±2.9%) or long-term maintenance GH therapy (7.0±3.1%). GH increased (<2 ng/dl to 22±4.3 ng/dl) and somatomedin (0.36±.20 to 1.3±.35 U/ml). An inverse correlation was noted between IRB, fasting insulin concentrations, and body weight:height ratios. Patients with high fasting insulin (>20 uU/ml) and low height:weight ratios had very low IRB (3.1±1.2%). IRB after GH treatment increased in patients in whom therapy was associated with an increase in body weight:height ratios. These data suggest IRB may be related to body fat stores rather than circulating GH concentration or somatomedin activity.

Log in or create a free account to read this content

Gain free access to this article, as well as selected content from this journal and more on nature.com

Access through your institution

or

Sign in or create an account

Continue with Google

Continue with ORCiD