Format

Send to

Choose Destination
Horm Metab Res. 2008 Jul;40(7):498-501. doi: 10.1055/s-2008-1065322. Epub 2008 Mar 31.

Contribution of gluconeogenesis and glycogenolysis to hepatic glucose production in acromegaly before and after pituitary microsurgery.

Author information

1
Department of Endocrinology, Metabolism and Diabetology Karolinska University Hospital, Stockholm, Sweden. charlotte.hoybe@karolinska.se

Abstract

The diabetogenic effect of excess growth hormone (GH) such as that in acromegaly is well known. However, the contribution of the various components to hepatic glucose production (HGP) is not completely understood. In this study we evaluated insulin resistance, HGP, gluconeogenesis (GNG), and glycogenolysis (GLY) in five patients with acromegaly before and after pituitary microsurgery. Insulin resistance was estimated by the HOMA index. HGP was measured using a primed continuous (6,6- 2H2) glucose infusion, and GNG was measured from 2 H enrichment at carbons 2 and 5 of blood glucose on ingestion of 2H2O. The ratio of these enrichments equals the fractional contribution of GNG to HGP, and GLY was calculated as the difference between HGP and GNG. All measurements were performed after 12 hours of fasting. Levels of GH and IGF-I decreased, as did the HOMA index (p<0.05). HGP was reduced from 11.4 micromol/kg/min to 9.7 micromol/kg/min (p=0.032). GNG contributed most to HGP. GNG was unchanged, whereas GLY's fraction decreased 29% (p=0.056) postoperatively. This pilot study indicates that GNG is the main contributor to HGP and that GLY is more sensitive than is GNG to the insulin resistance existing in acromegaly.

PMID:
18393170
DOI:
10.1055/s-2008-1065322
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Georg Thieme Verlag Stuttgart, New York
Loading ...
Support Center