Intravascular thrombosis in skeletal muscle microcirculation after ischemia.

This study was undertaken to elucidate the role of thrombosis in blood vessels less than 0.1 mm in diameter in skeletal muscle after an ischemic episode. Capillaries were examined after normothermic ischemia using intravital video microscopy of the cremaster muscle of an anesthetized rat. Histologic sections of the cremaster muscle and silicone rubber intravascular casts were also analyzed. Our model demonstrates that, after 3 hours of warm ischemia, up to two-thirds of capillaries are clotted, as is most of the venous system. Our findings also indicate that capillaries may reopen during 30 minutes of reperfusion. These findings suggest that ischemia may cause thrombosis in the microvasculature of skeletal muscle but the thrombosis appears to be partially reversible.