Muscle fiber capillarization as determining factor on indices of insulin sensitivity in humans

Muscle fiber capillarization as determining factor on indices of insulin sensitivity in humans

To investigate the association between muscle fiber capillarization and indices of insulin sensitivity in healthy older adults. A skeletal muscle biopsy was taken from the m vastus lateralis of 22 healthy (nondiabetic) male older adults. In addition, all participants underwent an Oral Glucose Tolerance Test (OGTT). Muscle fiber capillarization was assessed by immunohistochemistry. Participants ...

Increased skeletal muscle capillarization enhances insulin sensitivity.

Increased skeletal muscle capillarization is associated with improved glucose tolerance and insulin sensitivity. However, a possible causal relationship has not previously been identified. Therefore, we investigated whether increased skeletal muscle capillarization increases insulin sensitivity. Skeletal muscle-specific angiogenesis was induced by adding the α1-adrenergic receptor antagonist pr...

Increased Skeletal Muscle Capillarization Independently Enhances Insulin Sensitivity in Older Adults After Exercise Training and Detraining

Intramuscular signaling and glucose transport mechanisms contribute to improvements in insulin sensitivity after aerobic exercise training. This study tested the hypothesis that increases in skeletal muscle capillary density (CD) also contribute to exercise-induced improvements in whole-body insulin sensitivity (insulin-stimulated glucose uptake per unit plasma insulin [M/I]) independent of oth...

9 Fiber and Insulin Sensitivity

Insulin-mediated skeletal muscle vasodilation contributes to both insulin sensitivity and responsiveness in lean humans.

Whether insulin-mediated vasodilation is important in determining insulin's overall action to stimulate glucose uptake is unknown. To this end, we measured leg glucose uptake during euglycemic hyperinsulinemic clamps performed at two insulin doses (40 mU/m2 per min, n = 6 and 120 mU/m2 per min, n = 15) alone and during a superimposed intrafemoral artery infusion of GN-monomethyl-L-arginine (L-N...