Effect of 7 days of bed rest on dose-response relation between plasma glucose and insulin secretion.
Physical training decreases glucose-stimulated insulin secretion. To further explore the influence of the level of daily physical activity on beta-cell secretion, the effect of 7 days of bed rest was studied in six young, healthy men by sequential hyperglycemic clamp technique (7, 11, and 20 mM glucose, each step lasting 90 min). At 11 and 20 mM glucose, insulin concentrations in plasma were higher after (87 +/- 11 and 303 +/- 63 microU/ml) than before (63 +/- 5 and 251 +/- 50 microU/ml, P less than 0.05) bed rest. Also C-peptide levels were higher after bed rest than before during glucose stimulation. The responses of other hormones, metabolites, or electrolytes influencing beta-cell secretion were not influenced by bed rest. In spite of increased insulin levels after bed rest, glucose disposal at 20 mM of glucose was significantly lower after bed rest than before. It is concluded that bed rest for 7 days increases the glucose-stimulated insulin response, at least partly due to a beta-cell adaptation increasing glucose-stimulated insulin secretion. However, the insulin secretion does not increase adequately compared with the peripheral insulin resistance induced by bed rest.
Mikines
K J
KJ
Department of Medical Physiology B, Panum Institute, University of Copenhagen, Denmark.
Dela
F
F
Tronier
B
B
Galbo
H
H
D020155:3-Hydroxybutyric Acid; D000328:Adult; D000409:Alanine / Q000097:blood; D001510:Bed Rest; D001786:Blood Glucose / Q000378:metabolism*; D002096:C-Peptide / Q000097:blood; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005947:Glucose / Q000008:administration & dosage; D005990:Glycerol / Q000097:blood; D006801:Humans; D006885:Hydroxybutyrates / Q000097:blood; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007700:Kinetics; D007773:Lactates / Q000097:blood; D019344:Lactic Acid; D008297:Male; D010101:Oxygen Consumption; D011188:Potassium / Q000097:blood; D012964:Sodium / Q000097:blood; D014508:Urea / Q000097:blood
D001786:Blood Glucose; D002096:C-Peptide; D005230:Fatty Acids, Nonesterified; D006885:Hydroxybutyrates; D007328:Insulin; D007773:Lactates; D019344:Lactic Acid; D014508:Urea; D012964:Sodium; D005947:Glucose; D000409:Alanine; D005990:Glycerol; D011188:Potassium; D020155:3-Hydroxybutyric Acid