Marked increase in white adipose tissue blood perfusion in the type 2 diabetic GK rat

The aim of the present study was to evaluate and correlate islet to brown and white adipose tissue (WAT) blood perfusion in one obese rat and one nonobese rat with type 2 diabetes (obese Zucker (OZ] and GK rats, respectively). We measured blood perfusion with a microsphere technique in anesthetized animals and subsequently estimated the blood flow to seven different WAT depots and brown adipose tissue, in addition to the whole pancreas and pancreatic islets. Both GK and OZ rats had higher islet blood perfusion than their respective control strains. Adipose tissue blood flow (ATBF) was similar to or lower than that of controls in the normoglycemic OZ rats. GK rats, however, had 5-10 times higher blood perfusion than control Wistar rats in most WAT depots. Vascular density and macrophage numbers in WAT did not differ between the different strains. The discrepancy in ATBF between the obese-normoglycemic and type 2 diabetic rats opens the intriguing possibility that changes in this blood perfusion may influence and/or modulate the beta-cell dysfunction in type 2 diabetes.