Lumbar sympathectomy reduces vascular permeability, possibly through decreased adenosine receptor A2a expression in the hind plantar skin of rats

BACKGROUND: The effect of lumbar sympathectomy for the treatment of lower limb ischemia remains a matter of controversy. METHODS: Sprague-Dawley rats were subjected to lumbar sympathectomy, after which Evans blue dye was injected into the hind plantar skin. Extravasation of dye was measured and compared with rats undergoing sham operation. Hind plantar skin was processed for HE staining, immunohistochemistry, and Western blot. RESULTS: In sympathectomized rats, blue stained areas in hind plantar skin and concentrations of Evans blue were significantly less than that of sham sympathectomy (control) rats, both 2 weeks and 3 months after surgery. Expression of prostaglandin E2, bradykinin, bradykinin B2 receptor, and adenosine triphosphate were not significantly different between the sympathectomized and control groups. Adenosine receptor A2a expression was significantly reduced in the sympathectomized group both 2 weeks and 3 months after surgery. CONCLUSION: Vascular permeability in the hind plantar skin of rats decreases following lumbar sympathectomy, possibly via reduced expression of adenosine receptor A2a.