title: Interaction of glucagon and epinephrine in the control of hepatic glucose production in the conscious dog.
abstract: Epinephrine increases net hepatic glucose output (NHGO) mainly via increased gluconeogenesis, whereas glucagon increases NHGO mainly via increased glycogenolysis. The aim of the present study was to determine how the two hormones interact in controlling glucose production. In 18-h-fasted conscious dogs, a pancreatic clamp initially fixed insulin and glucagon at basal levels, following which one of four protocols was instituted. In G + E, glucagon (1.5 ng x kg(-1) x min(-1); portally) and epinephrine (50 ng x kg(-1) x min(-1); peripherally) were increased; in G, glucagon was increased alone; in E, epinephrine was increased alone; and in C, neither was increased. In G, E, and C, glucose was infused to match the hyperglycemia seen in G + E ( approximately 250 mg/dl). The areas under the curve for the increase in NHGO, after the change in C was subtracted, were as follows: G = 661 +/- 185, E = 424 +/- 158, G + E = 1178 +/- 57 mg/kg. Therefore, the overall effects of the two hormones on NHGO were additive. Additionally, glucagon exerted its full glycogenolytic effect, whereas epinephrine exerted its full gluconeogenic effect, such that both processes increased significantly during concurrent hormone administration.
authors.affiliation: Department of Molecular Physiology and Biophysics,Vanderbilt University, Nashville, Tennessee 37232, USA. stephanie.m.gustavson@vanderbilt.edu
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Gustavson
authors.forename: Chang An
authors.initials: CA
authors.lastname: Chu
authors.forename: Makoto
authors.initials: M
authors.lastname: Nishizawa
authors.forename: Ben
authors.initials: B
authors.lastname: Farmer
authors.forename: Doss
authors.initials: D
authors.lastname: Neal
authors.forename: Ying
authors.initials: Y
authors.lastname: Yang
authors.forename: E Patrick
authors.initials: EP
authors.lastname: Donahue
authors.forename: Paul
authors.initials: P
authors.lastname: Flakoll
authors.forename: Alan D
authors.initials: AD
authors.lastname: Cherrington
mesh_terms: D000409:Alanine / Q000097:blood / Q000493:pharmacokinetics; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D003243:Consciousness; D004285:Dogs; D004837:Epinephrine / Q000097:blood*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D005934:Glucagon / Q000378:metabolism*; D005943:Gluconeogenesis / Q000502:physiology; D005947:Glucose / Q000096:biosynthesis*; D005990:Glycerol / Q000097:blood; D006003:Glycogen / Q000378:metabolism; D006339:Heart Rate; D007659:Ketones / Q000097:blood; D019344:Lactic Acid / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male
chemical_list: D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007659:Ketones; D019344:Lactic Acid; D006003:Glycogen; D005934:Glucagon; D005947:Glucose; D000409:Alanine; D005990:Glycerol; D004837:Epinephrine