Abstract
Twelve volunteers were fasted overnight and infused with [13C]glucose (ul) to measure glucose production (GP), gluconeogenesis, and by subtraction,
glycogenolysis. Glucose production, gluconeogenesis, and glycogenolysis were measured
after a 3-hour baseline infusion and two 4-hour infusions. The first 4 hours of the
pituitary-pancreatic clamp study (PPCS) with replacement insulin, cortisol, and glucagon
was without growth hormone (GH) administration. The second 4 hours of the PPCS was
with high-dose GH administration. Six fasting volunteers acted as controls over the
11-hour study period. Overnight 12-hour fasting measurements of hormones, glucose,
GP, gluconeogenesis, and glycogenolysis were similar in both groups. The PPCS had
no significant effect on GP (2.43 ± 0.19 vs 2.07 ± 0.11 mg/kg per minute, PPCS vs
controls, mean ± SEM). Glycogenolysis, as a percent of GP (43%-49%), was similar between
PPCS and controls (43% ± 3% vs 49% ± 4%). High-dose GH for 4 hours increased GH (20.8
± 3.8 vs 2.0 ± 0.9 ng/mL), blood glucose (127 ± 28 vs 86 ± 4 mg/dL, P < .05), GP (2.21 ± 0.21 vs 1.81 ± 0.12 mg/kg per minute, P < .05). The increase in GP was due to sustained glycogenolysis as compared to the
observed fall in glycogenolysis seen with fasting alone (0.94 ± 0.21 vs 0.53 ± 0.07
mg/kg per minute, P < .05). Glycogenolysis, as a percent of GP, was significantly increased with high-dose
GH (43 ± 5% vs 29 ± 3%, P < .05). High-dose GH had no effect on gluconeogenesis (1.26 ± 0.15 vs 1.29 ± 0.12
mg/kg per minute). High-dose GH prevents the fall in glycogenolysis observed with
fasting alone.
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References
- Mechanism by which glucose and insulin inhibits net hepatic glycogenolysis in humans.J. Clin. Invest. 1998; 102: 1203-1209
- High insulin concentrations are required to suppress gluconeogenesis than glycogenolysis in nondiabetic humans.Diabetes. 2003; 52: 2213-2220
- Effects of low-dose and high-dose glucagon on glucose production and gluconeogenesis in humans.Metabolism. 2000; 49: 39-46
- Increased glucose turnover and glucose cycling in acromegalic patients with normal glucose tolerance.Diabetologia. 1986; 29: 778-783
- Insulin resistance in acromegaly: Defects in both hepatic and extrahepatic insulin action.Am. J. Physiol. 1986; 250: E269-E273
- Effects of hypopituitarism and growth hormone replacement therapy on the production and utilization of glucose in childhood.J. Clin. Endocrinol. Metab. 1985; 61: 1152-1157
- Influence of growth hormone on glucose induced glucose uptake in normal men as assessed by the hyperglycemic clamp technique.J. Clin. Endocrinol. Metab. 1989; 68: 276-282
- Mediation of the hepatic effects of growth hormone by its lipolytic activity.J. Clin. Endocrinol. Metab. 1999; 84: 1658-1663
- Short-term effects of growth hormone on fuel oxidation and regional substrate metabolism in normal man.J. Clin. Endocrinol. Metab. 1990; 70: 1179-1186
- The effect of growth hormone on glucose metabolism and insulin secretion in man.J. Clin. Endocrinol. Metab. 1982; 55: 973-982
- Gluconeogenesis and Cori cycle in 12, 20 and 40-hour fasted humans.Am. J. Physiol. 1998; 275: E537-E542
- The reciprocal pool model for the measurement of gluconeogenesis by use of [U-13C] glucose.Am. J. Physiol. 2000; 278: E140-E145
- Cortisol increases gluconeogensis in humans: Its role in the metabolic syndrome.Clin. Sci. 2001; 101: 739-747
- Contribution of cortisol to glucose counterregulation in humans.Am. J. Physiol. 1989; 257: E35-E42
- Effect of Metopirone and glucocorticoids on the glycogen content in the adrenal of rat fetuses.Ontogenez. 1976; 7: 638-642
- Growth hormone and glucose metabolism in lung cancer.Endocrine. 1994; 2: 1055-1059
- Glucose homeostasis in abdominal obesity: Hepatic hyper-responsiveness to growth hormone action.Am. J. Physiol. Endocrinol. Metab. 2004; 287: E63-E68
- Growth hormone and insulin binding to human liver.J. Clin. Endocrinol. Metab. 1976; 42: 484-488
- Alterations in insulin binding induced by changes in-vivo in the levels of glucocorticoids and growth hormone.Endocrinology. 1978; 105: 414-420
- Identification and characterization of high and low affinity binding sites for growth hormone in rabbit liver.Endocrinology. 1979; 105: 414-420
- Regulation of the hepatic response to glucagon: Role of insulin, growth hormone and cortisol.Horm. Res. 1989; 31: 244-249
- Growth hormone stimulates tyrosine phosphorylation of JAK2 and STAT5, but not insulin receptor substrate-1 or SHC proteins in liver and skeletal muscle of normal rats in-vivo.Endocrinology. 1996; 137: 2880-2886
- Effects of recombinant human growth hormone on hepatic lipid and carbohydrate metabolism in HIV-infected patients with fat accumulation.J. Clin. Endocrinol. Metab. 2002; 87: 942-945
- GH-mediated alteration of fuel metabolism in the aged rat as determined from transcript profiles.Physiol. Genomics. 2004; 16: 261-267
- Glucose production, recycling, Cori cycle and gluconeogenesis in humans: Relationship to serum cortisol concentrations.Am. J. Physiol. 1997; 272: E476-E484
- Glucose production, recycling, and gluconeogenesis in normals and diabetics: A mass isotopomer [U-13C] glucose study.Am. J. Physiol. 1996; 270: E709-E717
- Effects of free fatty acids per se on glucose production, gluconeogenesis, and glycogenolysis.Diabetes. 2003; 52: 260-267
- Effects of fasting and glucocorticoids on hepatic gluconeogenesis assessed using two independent methods in vivo.Am. J. Physiol. 2002; 283: E946-E957
Article info
Publication history
Accepted:
December 5,
2004
Received:
December 17,
2003
Footnotes
☆This grant was supported by the NIH Clinical Investigator Award KO8DK02083 and MO1-RR-00425.
Identification
Copyright
© 2005 Elsevier Inc. Published by Elsevier Inc. All rights reserved.
