Does endotoxin have an indirect vasodilatory effect on isolated human skeletal muscle arterioles?
This study demonstrates that endotoxin has no direct vasodilatory effect on human skeletal muscle arterioles, but it is the release of an endothelial factor from the upstream conduit vessels that produces the loss of tone in the microvasculature. Further research is ongoing to characterize the factors involved (nuclear factor-kappaB, tumor necrosis factor alpha, and interleuklin 6) for possible clinical intervention (antioxidants, cyclosporine, and nitric oxdide synthase inhibitors).
Our results substantiate evidence for an association between hypothyroidism and RAN. Potential mechanisms explaining this association are long-term hypertension, atherosclerotic processes, and inflammation.