Short-term effects of recombinant human growth hormone and feeding on gluconeogenesis in humans.
After a short-term fast, lactating women have increased rates of glucose production but not gluconeogenesis (GNG) despite relative hypoinsulinemia. We explored the effects of non-insulin-dependent increase in glucose utilization and recombinant human growth hormone (rhGH) on glucose production, glycogenolysis, and GNG in both the fed and overnight-fasted condition. Six controls and 7 lactating women were studied twice, in random order, after 7 days of saline or rhGH. Glucose kinetics and GNG were measured using [U-(13)C]glucose mass isotopomer distribution analysis. The rhGH increased milk production in the lactating women and insulin-like growth factor (IGF) in both groups. Glycogenolysis and GNG were higher in fasting lactating women than controls after either saline or rhGH (P < .05). After rhGH administration, GNG remained higher (P < .02) in the lactating women than controls. Gluconeogenesis was not suppressed in either group during 5 hours of continuous meal ingestion, despite a 5-fold increase in plasma insulin. Lactating women had similar glucose but lower insulin and C-peptide concentrations than controls after both rhGH and saline treatment (P < .01), although rhGH decreased (P < .01) insulin sensitivity in both groups (P < .05). Gluconeogenesis is not affected by short-term increases in insulin and/or rhGH, which suggests a fundamental rethinking of the role of insulin in acutely regulating GNG.
Kaplan
Walid
W
Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX 77030-2600, USA.
Sunehag
Agneta L
AL
Dao
Harry
H
Haymond
Morey W
MW
D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D004435:Eating; D005215:Fasting / Q000378:metabolism; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D005943:Gluconeogenesis / Q000187:drug effects*; D019382:Human Growth Hormone / Q000494:pharmacology*; D006801:Humans; D007333:Insulin Resistance; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D007774:Lactation / Q000187:drug effects; D011994:Recombinant Proteins / Q000494:pharmacology
D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D011994:Recombinant Proteins; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I