Experimental free muscle transplantation. Is autologous graft on the distal esophagus viable

Experimental free muscle transplantation has resulted in some successful clinical applications. AIM: The possibility that this type of transplantation could act as a sphincteric mechanism motivated us to start by assessing the viability of autologous skeletal grafts on the distal esophagus of laboratory animals. MATERIAL AND METHODS: Twenty transplants of previously denervated free plantaris muscle grafted on the distal esophagus of Sprague-Dawley rats were evaluated at the 1st, 2nd, 4th, 8th and 16th posttransplant week. Histological and histochemical studies were performed to evaluate general features of the grafts and the muscle fibers condition. RESULTS: One and two weeks after transplant the grafts show large areas of necrosis with inflammatory infiltrate. Between the 2nd and the 4th week, as revascularization and motor endplates become significant, the areas of necrosis begin to regress and they almost disappear by the 8th week. Since the 4th week after transplant, regenerated muscle fibers demonstrate morphological and biochemical features similar to normal. CONCLUSIONS: Experimental free plantaris muscle transplantation on the distal esophagus is viable and shows revascularized and reinnervated muscle fibers from the 8th week after transplant on, and at least until the 16th. These fibers have the structural and metabolic properties enabling contractile function. This original model may allow further investigation of some features related to pathophysiology and therapy of gastroesophageal reflux.