Life Sciences Commons^™

Hypoxia-Sensitive Gene Expression In The Gastrocnemius Muscle Following Chronic Hind Limb Ischemia, Andrew Tilton

Biological Sciences

Chronic ischemia, caused by the formation atherosclerotic plaque occlusions in major conduit arteries, is the leading cause of morbidity and mortality in western societies. Vascular remodeling can help compensate for the adverse effects of atherosclerotic plaque formation. Vascular remodeling relies heavily on vascular endothelial growth factor (VEGF), a critical protein that contributes to all forms of vascular formation and remodeling including angiogenesis, arteriogenesisand vasculogenesis. VEGF itself is up-regulated by the transcription factor, hypoxia inducible factor 1 alpha (HIF-1α), which becomes activated in low oxygen environments.

Through the use of animal chronic hindlimb ischemia models, these genes can be evaluated as …

Ischemia Impairs Vasodilation In Skeletal Muscle Resistance Artery, Kyle Remington Struthers

Master's Theses

Functional vasodilation in arterioles is impaired with chronic ischemia. We sought to examine the impact of chronic ischemia and age on skeletal muscle resistance artery function. To examine the impact of chronic ischemia, the femoral artery was resected from young (2-3mo) and adult (6-7mo) mice and the profunda femoris artery diameter was measured at rest and following gracilis muscle contraction 14 days later using intravital microscopy. Functional vasodilation was significantly impaired in ischemic mice (14.4±4.6% vs. 137.8±14.3%, p<0.0001 n=8) and non-ischemic adult mice (103.0±9.4% vs. 137.8±14.3%, p=0.05 n=10). In order to analyze the cellular mechanisms of the impairment, a protocol was developed to apply pharmacological agents to the experimental preparation while maintaining tissue homeostasis. Endothelial and smooth muscle dependent vasodilation were impaired with ischemia, 39.6 ± 13.6% vs. 80.5 ± 11.4% and 43.0 ± 11.7% vs. 85.1 ± 10.5%, respectively. From this data, it can be supported that smooth muscle dysfunction is the reason for the observed impairment in arterial vasodilation.