The effects of epinephrine on ketogenesis in the dog after a prolonged fast.
The effects of a selective increase in epinephrine on ketogenesis and lipolysis were determined in the conscious dog following a prolonged fast (7 days). Plasma insulin and glucagon were fixed at basal levels by infusion of somatostatin (0.8 micrograms/kg/min) and basal intraportal replacement amounts of insulin (210 +/- 20 microU/kg/min) and glucagon (0.65 ng/kg/min). Following a 40-minute control period, saline or epinephrine (0.04 microgram/kg/min) was infused for 3 hours. Plasma insulin, glucagon, and norepinephrine levels did not change during saline (6 +/- 1 microU/mL, 83 +/- 17 pg/mL, and 137 +/- 38 pg/mL, respectively) or epinephrine (10 +/- 1 microU/mL, 73 +/- 18 pg/ml, 98 +/- 13 pg/mL, respectively) infusion. Plasma epinephrine levels increased from 80 +/- 26 to 440 +/- 47 pg/mL in response to infusion of the catecholamine, but remained unchanged during saline infusion. Glycerol levels (93 +/- 10 mumol/L) remained unchanged during saline infusion, but increased in response to epinephrine (108 +/- 9 to 170 +/- 18 mumol/L by 30 minutes). The glycerol level had returned to baseline and to the value apparent in saline controls by 60 minutes. The nonesterified fatty acid (NEFA) level declined slowly during the 3-hour saline infusion, but was elevated in response to epinephrine infusion (1.27 +/- 0.16 to 1.97 +/- 0.25 mmol/L at 30 minutes). After the initial epinephrine-induced increase, the NEFA level declined so that by 3 hours it was not significantly different from the basal or saline values.(ABSTRACT TRUNCATED AT 250 WORDS)
Steiner
K E
KE
Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232-0615.
Stevenson
R W
RW
Adkins-Marshall
B A
BA
Cherrington
A D
AD
D000818:Animals; D002395:Catecholamines / Q000097:blood; D004285:Dogs; D004837:Epinephrine / Q000502:physiology*; D005215:Fasting; D005230:Fatty Acids, Nonesterified / Q000378:metabolism; D005260:Female; D005990:Glycerol / Q000378:metabolism; D007657:Ketone Bodies / Q000096:biosynthesis* / Q000378:metabolism; D008066:Lipolysis; D008099:Liver / Q000378:metabolism; D008297:Male; D010187:Pancreatic Hormones / Q000097:blood; D013997:Time Factors
D002395:Catecholamines; D005230:Fatty Acids, Nonesterified; D007657:Ketone Bodies; D010187:Pancreatic Hormones; D005990:Glycerol; D004837:Epinephrine