Hormonal control of substrate cycling in humans.

摘要: Recent studies have established the existence of substrate cycles in humans, but factors regulating rate cycling not been identified. We therefore investigated acute response glucose/glucose-6P-glucose (glucose) and triglyceride/fatty acid (TG/FA) to infusion epinephrine (0.03 microgram/kg.min) glucagon. The a high dose glucagon (2 micrograms/kg.min) was tested, as well low (5 ng/kg.min), with without simultaneous somatostatin (0.1 insulin mU/kg.min). Additionally, chronic prednisone (50 mg/d) evaluated, both alone during (low dose) infusion. Finally, hyperglycemia, held constant by replacement at basal rates, investigated. Glucose calculated difference between appearance (Ra) glucose determined using 2-d1- 6,6-d2-glucose tracers. TG/FA first determining Ra glycerol d5-glycerol FFA [1-13C]palmitate, then subtracting from three times glycerol. results indicate that stimulates cycling, this stimulatory effect is augmented when blocked. Glucagon had minimal on cycling. In contrast, stimulated affected minimally. Prednisone no direct either or blunted Hyperglycemia, per se, Calculations revealed stimulation theoretically amplified sensitivity control fatty flux, such amplification evident result