The effect on adipose tissue blood flow of isoenergetic meals containing different amounts and types of fat.

OBJECTIVE: To investigate the factors regulating the increase in adipose tissue blood flow following meals. DESIGN: Eight subjects were fed three isoenergetic meals; two high-fat meals rich in either saturated or polyunsaturated fatty acids and one low-fat, high-carbohydrate meal. MEASUREMENTS: Blood samples were taken and adipose tissue blood flow was measured before and for 6 h after the meal. Plasma glucose, insulin, non-esterified fatty acid, total and chylomicron-triacylglycerol and catecholamine concentrations were measured. RESULTS: Adipose tissue blood flow rose to a peak after all three meals (P<0.05 for each). The three meals stimulated adipose tissue blood flow at similar times. There was a marked and statistically significant similarity in the time course of changes in blood flow and insulin concentrations. In contrast, noradrenaline concentrations peaked later than adipose tissue blood flow (P=0.014). CONCLUSION: Adipose tissue blood flow may be 'carbohydrate-stimulated' rather than 'fat-stimulated', with insulin having a vasodilatory role in adipose tissue as in skeletal muscle