UNLABELLED: Postprandially, the blood flow and uptake of non-esterified fatty acids increase concomitantly in the abdominal subcutaneous adipose tissue in healthy subjects. In insulin-resistant subjects, this postprandial blood flow increase is blunted. We have previously found that the postprandial adipose tissue blood flow (ATBF) increase is accompanied by capillary recruitment in healthy subjects. The aim of the present study was to investigate whether the postprandial capillary recruitment in adipose tissue is affected in type 2 diabetes mellitus. Eight type 2 diabetic overweight male subjects and eight age- and weight-matched healthy subjects were studied. Contrast-enhanced ultrasound imaging was applied to study the microvascular volume in abdominal subcutaneous adipose tissue and in forearm skeletal muscle in the fasting state and 60, 120 and 180 min after a 75-g oral glucose load. Abdominal subcutaneous ATBF was measured using (133) Xenon washout technique, and forearm skeletal muscle blood flow was assessed by venous occlusion plethysmography. In the healthy, overweight subjects, ATBF increased and concomitantly capillary recruitment took place after glucose ingestion. No significant changes were found in the ATBF or in capillary recruitment in the type 2 diabetic subjects. There was no significant blood flow or microvascular blood volume changes in forearm skeletal muscle in either of the groups.

CONCLUSION: After an oral glucose load, the abdominal ATBF and microvascular blood volume changes in abdominal subcutaneous adipose tissue are impaired in overweight type 2 diabetic subjects compared to weight-matched healthy subjects.