AJP - Endocrinology and Metabolism, Vol 267, Issue 3 E454-E460, Copyright © 1994 by American Physiological Society
Effect of growth hormone on hepatic glucose and insulin metabolism after oral glucose in conscious dogs
Y. Okuda, J. Pena, J. Chou and J. B. Field
Department of Medicine, St. Lukes Episcopal Hospital, Baylor College of Medicine, Houston, Texas 77225-0269.
This study examined the effect of growth hormone (GH) on hepatic glucose
metabolism and on the fractional extraction of insulin and glucagon after
oral glucose administration. GH treatment [canine GH (0.75 mg/day for 7
days)] significantly increased basal portal vein and hepatic artery flow (P
< 0.01 compared with pre-GH treatment). After GH treatment and after
oral glucose, glucose levels significantly exceeded those before GH at 100
and 120 min in arterial and portal vein plasma and 120 min in the hepatic
vein. The net hepatic uptake of glucose was similar before and after GH
treatment. The increment of net nonhepatic splanchnic insulin balance above
basal was 131 +/- 31 mU.kg-1.3 h-1 before and 272 +/- 46 mU.kg-1.3 h-1
after GH treatment (P < 0.05). An increase in fractional hepatic
extraction of insulin occurred before GH treatment and was significantly
greater at 60 min. In summary, despite the increased insulin content after
GH administration, there was no change in hepatic uptake of glucose,
indicating that the liver was also the site of insulin resistance.
