OBJECTIVE -The relationship between splanchnic glucose uptake (SGU) after oral glucose administration and metabolic control in type 1 diabetic patients is controversial. We estimated SGU as well as peripheral glucose uptake and the time required for glucose absorption by a validated method, the oral glucose (OG) clamp, in type 1 diabetic patients with different levels of long-term glycemic control. ⅐ min Ϫ1 in DP (NS). Glucose absorption was 140 Ϯ 6 min in C, 156 Ϯ 4 min in DG, and 143 Ϯ 7 min in DP (NS). The respective calculated SGU was 14.5 Ϯ 5.6% in C, 17.8 Ϯ 3.1% in DG, and 18.8 Ϯ 4.2% in DP (NS) and did not correlate with HbA 1c values.
RESEARCH DESIGN AND METHODSCONCLUSIONS -Peripheral glucose uptake, SGU after oral glucose administration, and the glucose absorption time were not different in type 1 diabetic patients independent of glycemic control when compared with healthy subjects.
Diabetes Care 25:2042-2047, 2002I n the interprandial state, plasma glucose concentrations are determined by hepatic glucose production and peripheral glucose utilization. After glucose ingestion, the liver switches from glucose production to glucose uptake (1). The magnitude of hepatic glucose uptake is regulated by several factors, such as the amount of glucose administered (2), the route of glucose administration (3-5), and hormonal factors such as the portal relation of insulin and glucagon (2,6,7).It has been shown that hepatic glucose uptake is greater after oral or intraportal glucose administration than after peripheral glucose infusion because of a negative arterial-portal glucose gradient (2-5,8 -12). Increased net hepatic glucose uptake has furthermore been observed in the presence of hyperglycemia at basal (3) as well as at elevated insulin levels (2,6,11).Direct measurement of hepatic glucose uptake is not feasible in humans because the portal vein cannot be cannulated. Therefore, indirect methods measuring splanchnic glucose uptake (SGU), which includes the uptake of glucose by the gut, have been developed. Currently, there are three methods used to estimate SGU in humans. Hepatic vein catheterization allows the measurement of net hepatic glucose output on the systemic side of the liver glucose (1,13). The application of this method, however, is limited by its invasive nature and by radiation exposure. The double-tracer technique uses different tracers to distinguish the ingested glucose from the systemic pool. However, results obtained with this method can be affected by incorporation of glucose tracers into glycogen, which can cause inaccurate calculation of the glucose appearance rate (14). The oral glucose (OG) clamp technique was developed and validated against the hepatic Abbreviations: C, control subjects; DG, type 1 diabetic patients with good metabolic control; DP, type 1 diabetic patients with poor metabolic control; GINF, glucose infusion rate; GINF OG , GINF during oral glucose absorption; GINF(t), GINF during resorption time; OG, oral glucose; OGL, OG load; SGU, splanchnic glucose uptake.A table el...