Interaction of equal increments in arterial and portal vein insulin on hepatic glucose production in the dog.
We have previously shown that a selective increase of 84 pmol/l in either arterial or portal vein insulin (independent of a change in insulin in the other vessel) can suppress tracer-determined glucose production (TDGP) and net hepatic glucose output (NHGO) by approximately 50%. In the present study we investigated the interaction between equal increments in arterial and portal vein insulin in the suppression of TDGP and NHGO. Isotopic ([3-3H]glucose) and arteriovenous difference methods were used in conscious overnight fasted dogs. A pancreatic clamp was used to control the endocrine pancreas. A 40-min basal period was followed by a 180-min test period, during which arterial and portal vein insulin levels were simulataneously and equally increased 102 pmol/l. Hepatic sinusoidal glucagon levels remained unchanged, and euglycemia was maintained by peripheral glucose infusion. TDGP was suppressed approximately 60% by the last 30 min of the experimental period. In contrast, NHGO was suppressed 100% by that time. Coincidentally, hepatic glucose uptake (net hepatic [3H]glucose balance) increased significantly (approximately 4 mumol.kg-1.min-1). The effects of simultaneous equal increases in peripheral and portal venous insulin were not additive in the suppression of TDGP. However, they were additive in decreasing NHGO as a result of an increase in the uptake of glucose by the liver.
Sindelar
D K
DK
Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0615, USA.
Chu
C A
CA
Neal
D W
DW
Cherrington
A D
AD
D020155:3-Hydroxybutyric Acid; D000090:Acetoacetates / Q000097:blood / Q000378:metabolism; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D004285:Dogs; D005230:Fatty Acids, Nonesterified / Q000097:blood / Q000378:metabolism; D005260:Female; D005934:Glucagon / Q000097:blood; D005943:Gluconeogenesis; D005947:Glucose / Q000096:biosynthesis / Q000378:metabolism*; D005990:Glycerol / Q000097:blood / Q000378:metabolism; D006499:Hepatic Artery / Q000502:physiology*; D006885:Hydroxybutyrates / Q000097:blood / Q000378:metabolism; D007328:Insulin / Q000097:blood* / Q000502:physiology; D007515:Islets of Langerhans / Q000502:physiology; D007773:Lactates / Q000097:blood / Q000378:metabolism; D008099:Liver / Q000098:blood supply* / Q000378:metabolism*; D008297:Male; D011169:Portal Vein / Q000502:physiology*; D011865:Radioisotope Dilution Technique; D014316:Tritium
D000090:Acetoacetates; D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D006885:Hydroxybutyrates; D007328:Insulin; D007773:Lactates; D014316:Tritium; C016635:acetoacetic acid; D005934:Glucagon; D005947:Glucose; D005990:Glycerol; D020155:3-Hydroxybutyric Acid