Effects of Type II diabetes on capillary hemodynamics in skeletal

Microcirculatory red blood cell (RBC) hemodynamics are impaired within skeletal muscle of Type I diabetic rats (Kindig CA, Sexton WL, Fedde MR, and Poole DC. Respir Physiol 111: 163–175, 1998). Whether muscle microcirculatory dysfunction occurs in Type II dia-betes, the more prevalent form of the disease, is unknown. We hypothesized that Type II diabetes would reduce the proportion of capillaries supporting continuous RBC flow and RBC hemodynamics within the spinotrapezius muscle of the Goto-Kakizaki Type II diabetic rat (GK). With the use of intravital microscopy, muscle capillary diameter (dc), capillary lineal density, capillary tube hematocrit (Hctcap), RBC flux (FRBC), and velocity (VRBC) were measured in healthy male Wistar (control: n 5, blood glucose, 105 5 mg/dl) and male GK (n 7, blood glucose, 263 34 mg/dl) rats under resting conditions. Mean arterial pressure did not differ between groups (P 0.05). Sarcomere length was set to a physiological lengt