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- Fugmann, Andreas, et al.
(författare)
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Blood flow is an important determinant of forearm glucose uptake following a mixed meal
- 2003
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Ingår i: Acta Diabetologica. - : Springer Science and Business Media LLC. - 0940-5429 .- 1432-5233. ; 40:3, s. 113-117
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Tidskriftsartikel (refereegranskat)abstract
- Insulin-mediated vasodilation has been suggested to be of importance for glucose uptake during normoglycemic hyperinsulinemia. If this also is valid after an ordinary mixed meal remains to be evaluated. Forearm blood flow (FBF) and forearm glucose uptake change (evaluated by venous occlusion plethysmography) and glucose arteriovenous differences were evaluated over 120 minutes in 10 healthy volunteers following an ordinary mixed meal (700-900 kcal, 34% of energy from fat). Fasting arterial glucose level was 4.9+/-0.9 mmol/l, and the maximum glucose level was reached 30 minutes after the start of ingestion (6.6+/-0.8 mmol/l, p<0.0001). Plasma insulin levels were increased four-fold. FBF increased rapidly within 20 minutes after the start of ingestion and reached its maximum after 50 minutes (94% higher than baseline level, p<0.01). After 2 hours FBF was still substantially elevated (75% above baseline level, p<0.01). Forearm glucose uptake increased fivefold already after 20 minutes ( p<0.01). During the 2 hours, the increase in FBF contributed to 41% of the forearm glucose uptake ( p<0.05). The present study showed that the increase in FBF seen after an ordinary mixed meal is important for the change in forearm glucose uptake. These results support the view that modulation of limb blood flow is a determinant of glucose uptake.
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| 2. |
- Fugmann, Andreas, et al.
(författare)
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The effect of euglucaemic hyperinsulinaemia on forearm blood flow and glucose uptake in the human forearm
- 1998
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Ingår i: Acta Diabetologica. - : Springer Science and Business Media LLC. - 0940-5429 .- 1432-5233. ; 35:4, s. 203-206
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Tidskriftsartikel (refereegranskat)abstract
- Insulin-mediated stimulation of blood flow to skeletal muscle has been proposed to be of major importance for insulin-mediated glucose uptake. The aim of this study was to investigate the relative importance of blood flow and glucose extraction as determinants of insulin-mediated glucose uptake in the human forearm. Forearm blood flow (FBF), glucose extraction and oxygen consumption were evaluated for 100 min during the euglycaemic hyperinsulinaemic clamp (92 mU/l) in nine healthy subjects. FBF was measured by venous occlusion plethysmography. Forearm glucose uptake increased sevenfold during the hyperinsulinaemia (P<0.001). Forearm glucose extraction showed a minor increase during the first 10 min of hyperinsulinaemia, but the most marked increase took place between 10 and 20 min (+170%). Thereafter, only a minor further increase was seen. During the first 10 min of hyperinsulinaemia FBF was unchanged. Thereafter, FBF increased steadily to a plateau reached after 60 min (+50%, P<0.001). A close relationship between whole body glucose uptake and FBF was seen at the end of the clamp (r = 0.75, P<0.02), but at this time the relationship between whole body glucose uptake and forearm glucose extraction was not significant. The modest increase in O2 consumption seen at the beginning of the clamp (+19%) was not related to FBF during the early phase of the clamp. In conclusion, the early course of insulin-mediated glucose uptake in the human forearm was mainly due to an increase in glucose extraction. However, with time the insulin-mediated increase in blood flow increased in importance and after 100 min of hyperinsulinaemia FBF was the major determinant of glucose uptake.
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