The role of splanchnic glucose output in determining glycemic responses after mixed meal in type II diabetic patients and normal subjects.

Postprandial serum glucose concentrations are determined by both the rates of glucose appearance and disposal in normal subjects and diabetic patients. The significance of each parameter following mixed meal remains controversial. We have compared the serum glucose and C-peptide responses, as well as glucose fluxes (D[3-3H]glucose technique), after a breakfast mixed meal in type II diabetic patients (n = 6) and normal subjects (n = 7). The mean (+/- SEM) fasting serum glucose and postprandial glycemic responses were significantly (p less than 0.001) higher in the diabetic patients compared with the normal subjects. Mean fasting serum C-peptide levels were similar in both groups. After the mixed meal ingestion, serum C-peptide levels were significantly higher at 20 min (p less than 0.02) and 40 min (p less than 0.01) in the normal subjects compared with diabetic patients. The mean basal hepatic glucose output was 124 +/- 15 vs. 70 +/- 6 mg/m2 min (p less than 0.001) in the diabetics compared with the normal subjects, respectively. After mixed meal ingestion, the incremental integrated areas and rates of splanchnic glucose appearance (RA) and utilization (RU) were significantly (p less than 0.001) higher in the diabetics versus normal subjects. Both basal and post-meal metabolic clearance rate (MCR) were significantly (p less than 0.05) lower in the diabetic patients when compared with the normal subjects.(ABSTRACT TRUNCATED AT 250 WORDS)