Characterization of the insulin-antagonistic effect of growth hormone in man

✍ Scribed by J. Fowelin; S. Attvall; H. von Schenck; U. Smith; I. Lager

• Publisher: Springer
• Year: 1991
• Tongue: English
• Weight: 666 KB
• Volume: 34
• Category: Article
• ISSN: 0012-186X
• DOI: 10.1007/bf00403286

✦ Synopsis

The insulin-antagonistic effect of growth hormone was characterized by infusing the hormone at three different infusion rates (6, 12 or 24mU.kg-*.min -1) for one h in 11 healthy subjects. The insulin effect was measured with the euglycaemic clamp technique combined with D-(3-3H)-glucose infusion to evaluate glucose production and utilization. A control study with NaC1 (154 mmol. 1 1) infusion was also performed. The insulin levels during the clamps were similar in all studies (36 + 0.2 mU-1 1). Peak growth hormone levels were reached at 60 min (growth hormone 6 mU. kg-1. h-l: 31 + 5; growth hormone 12 mU. kg 1. h-l: 52 + 4 and growth hormone 24 mU. kg -1. h-l: 102 + 8 mU. 1-0. The insulinantagonistic effect of growth hormone started after -2 h, was maximal after 4-5 h (-39% inhibition of glucose infusion rate between control and growth hormone 24 mU-kg -1. h-1) and lasted for 6-7 h after peak levels. The resistance was due to a less pronounced insulin effect both to inhibit glucose pro-duction and to stimulate glucose utilization. Growth hormone infusion of 12 mU. kg -I. h -1 induced a similar insulinantagonistic effect as the higher infusion rate whereas 6 mU. kg-1. h -1 induced a smaller response with a duration of 1 h between 3-4 h after peak levels of growth hormone. The present study demonstrates that growth hormone levels similar to those frequently seen in Type 1 (insulin-dependent) diabetic patients during poor metabolic control or hypoglycaemia, have pronounced insulin-antagonistic effects. The effects starts after about 2-3 h, is maximal after 4-5 h and lasts for about 6-7 h. Both duration and inhibitory effect of growth hormone are related to the plasma levels, where a maximal effect is seen at about 50 mU. 1 ~ or higher.