Blood flow is an important determinant of forearm glucose uptake following a mixed meal

Abstract.   Insulin-mediated vasodilation has been suggested to be ofimportance for glucose uptake during normoglycemichyperinsulinemia. If this also is valid after an ordinary mixedmeal remains to be evaluated. Forearm blood flow (FBF) andforearm glucose uptake change (evaluated by venous occlusionplethysmography) and glucose arteriovenous differences wereevaluated over 120 minutes in 10 healthy volunteers following anordinary mixed meal (700–900 kcal, 34% of energy from fat).Fasting arterial glucose level was 4.9±0.9 mmol/l, and themaximum glucose level was reached 30 minutes after the start ofingestion (6.6±0.8 mmol/l, p<0.0001). Plasma insulin levelswere increased four-fold. FBF increased rapidly within 20minutes after the start of ingestion and reached its maximumafter 50 minutes (94% higher than baseline level,p<0.01). After 2 hours FBFwas still substantially elevated (75% above baseline level,p<0.01). Forearm glucoseuptake increased fivefold already after 20 minutes (p<0.01). During the 2 hours, theincrease in FBF contributed to 41% of the forearm glucose uptake(p<0.05). The presentstudy showed that the increase in FBF seen after an ordinarymixed meal is important for the change in forearm glucoseuptake. These results support the view that modulation of limbblood flow is a determinant of glucose uptake.