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- Nygren, Jonas O., et al.
(författare)
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Perioperative insulin and glucose infusion maintains normal insulin sensitivity after surgery
- 1998
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Ingår i: American Journal of Physiology. - : American Physiological Society. - 0002-9513 .- 2163-5773. ; 275:1 Part 1, s. E140-E148
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Tidskriftsartikel (refereegranskat)abstract
- Elective surgery was performed after overnight fasting, a routine that may affect the metabolic response to surgery. We investigated the effects of insulin and glucose infusions before and during surgery on postoperative substrate utilization and insulin sensitivity. Seven patients were given insulin and glucose infusions 3 h before and during surgery (insulin group), and a control group of six patients underwent surgery after fasting overnight. Insulin sensitivity and glucose kinetics (D-[6,6-2H2]glucose) were measured before and immediately after surgery using a hyperinsulinemic, normoglycemic clamp. Glucose infusion rates and whole body glucose disposal decreased after surgery in the control group (-40 and -29%, respectively), whereas no significant change was found in the insulingroup (+16 and +25%). Endogenous glucose production remained unchanged in both groups. Postoperative changes in cortisol, glucagon, fat oxidation, and free fatty acids were attenuated in the insulin group (vs. control). We conclude that perioperative insulin and glucose infusions minimize the endocrine stress response and normalize postoperative insulin sensitivity and substrate utilization.
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| 2. |
- Nygren, Jonas, et al.
(författare)
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Short-term hypocaloric nutrition but not bed rest decrease insulin sensitivity and IGF-I bioavailability in healthy subjects : the importance of glucagon
- 1997
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Ingår i: Journal of Nutrition. - : Oxford University Press. - 0022-3166 .- 1541-6100. ; 13:11-12, s. 945-951
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Tidskriftsartikel (refereegranskat)abstract
- Hyperinsulinemic, normoglycemic clamps were performed before and after 24 h of either hypocaloric nutrition or bed rest in healthy subjects. Decreased insulin sensitivity and insulin-like growth factor-I (IGF-I) bioavailibility, as measured by the serum IGF-I/insulin-like growth factor binding protein-1 (IGFBP-1) ratio, was found after fasting, whereas no metabolic changes were found after bed rest. Glucagon seems to be a key regulator of IGFBP-1 after brief hypocaloric nutrition. Hypocaloric nutrition and immobilization may add to the catabolic response to surgery and other trauma. Presently, six healthy subjects were studied before and after a 24-h period of hypocaloric nutrition (200 kcal/24 h, fast) or immobilization (bed rest) using the hyperinsulinemic (0.8 mU · kg−1 · min−1), normoglycemic (4.5 mmol/L) clamp, indirect calorimetry, and circulating levels of substrates and hormones. After fast, body weight decreased (P < 0.05), and nitrogen balance was negative (−10 ± 1 g urea nitrogen/24 h). Basal levels of free fatty acids, glucagon, and IGFBP-1 increased (P < 0.05), whereas c-peptide levels and the IGF-I/IGFBP-1 ratio decreased (P < 0.05). However, no change was found in basal levels of IGF-I or substrate oxidation. Furthermore, changes (%) in basal levels of glucagon after fast correlated to IGFBP-1 (r = 1.0, P < 0.05), whereas the suppressibility of IGFBP-1 by insulin was maintained at normal levels. During clamps, glucose infusion rates (GIR) decreased after fast (−43 ± 13%, mean ± SEM, P < 0.001). Although not significant, clamp levels of fat oxidation tended to increase and glucose oxidation tended to decrease. Levels of IGFBP-1 during clamps were higher as compared with the control clamp (P < 0.05). No adverse metabolic changes were seen after bed rest, and no change in GIR during clamps were seen as compared with the control measurement (0 ± 14%). After brief hypocaloric nutrition, insulin sensitivity is reduced, whereas IGF-I bioavailibility is reduced by an increase in levels of IGFBP-1. Glucagon seems to contribute to the increase in IGFBP-1 during these conditions.
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