PYY and Hyperglycemia: We demonstrate that (1) skeletal muscle MBF decreases with an OGTT and increases with an IVGTT when matched for similar blood glucose excursions; (2) these opposing vascular actions are not related to hyperglycaemia per se; (3) plasma levels of the incretin hormone GIP are strongly associated with impaired microvascular responses in skeletal muscle, whereas (4) plasma PYY and ghrelin are not associated with MBF.