Tissue-plasminogen activator restores muscle flap perfusion in the rat

This study was designed to evaluate the effect of tissue-plasminogen activator on skeletal muscle flap perfusion after a thrombogenic insult. Twenty-four male Sprague-Dawley rats were divided into 4 experimental groups of 6 animals each. In group 1 (sham), the cremaster muscle was isolated as an end-organ flap. In group 2, after cremaster muscle isolation, a semicircular inverted suture as a thrombogenic insult was performed at the ipsilateral common iliac artery. In group 3, local tissue-plasminogen activator infusion followed the inverted suture. In group 4, vehicle was infused. After 24 hours, the cremaster muscle flap hemodynamics and leukocyte-endothelial interactions were measured using intravital microscopy. Capillary perfusion significantly decreased after the inverted suture from a median of 6.23 (group 1) to 1.50 (group 2) functional capillaries per visual field. Tissue-plasminogen activator significantly increased capillary perfusion after the thrombogenic insult from a median of 1.50 (group 2) and 2.50 (group 4) to 6.00 (group 3). Tissue-plasminogen activator restored capillary perfusion after a thrombogenic insult to the main feeding artery.