Rapid changes in hepatic glucose output after a pulse of growth hormone in dogs.
In response to a single intravenous injection of bovine growth hormone (GH, 100 micrograms/kg) the non-steady-state turnover of glucose, as well as portal levels of insulin (IRI), glucagon (IRG), somatostatin (SRIF), and glucose were determined in normal conscious dogs. Using the two-compartment model validated to calculate rapid turnover changes and tracer infusion methods, the rate of hepatic output of glucose [Ra(t)] was found to be increased, reaching a maximum of 224 mg/min, 7.4 times the basal rate, 4 min after injection of GH. Ra(t) returned to its basal level 35 min later in a damped oscillatory manner. Hormone determinations were carried out in portal venous blood drawn every 2 min for 2 h from an indwelling catheter. IRG peaked 2 min after GH injection and levels of IRI, SRIF, and glucose peaked between 4 and 8 min. Hormone concentrations returned to normal, i.e., were oscillating around base-line levels, about 30 min after GH. These experiments demonstrate for the first time in vivo that a pulse of GH causes transient changes of glucose turnover and measurable alterations of the hormonal homeostasis in the splanchnic area.
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D004285:Dogs; D005260:Female; D005934:Glucagon / Q000097:blood; D005947:Glucose / Q000378:metabolism*; D013006:Growth Hormone / Q000494:pharmacology*; D007328:Insulin / Q000097:blood; D007700:Kinetics; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D013004:Somatostatin / Q000097:blood
D001786:Blood Glucose; D007328:Insulin; D013004:Somatostatin; D013006:Growth Hormone; D005934:Glucagon; D005947:Glucose