Dhawan Vikas, Lytle Ian F, Dow Douglas E, Huang Yen-Chih, Brown David L
Section of Plastic and Reconstructive Surgery, University of Michigan, Ann Arbor, Michigan 48109, USA.
Tissue Eng. 2007 Nov;13(11):2813-21. doi: 10.1089/ten.2007.0003.
Engineered functional skeletal muscle would be beneficial in reconstructive surgery. Our previous work successfully generated 3-dimensional vascularized skeletal muscle in vivo. Because neural signals direct muscle maturation, we hypothesized that neurotization of these constructs would increase their contractile force. Additionally, should neuromuscular junctions (NMJs) develop, indirect stimulation (via the nerve) would be possible, allowing for directed control. Rat myoblasts were cultured, suspended in fibrin gel, and implanted within silicone chambers around the femoral vessels and transected femoral nerve of syngeneic rats for 4 weeks. Neurotized constructs generated contractile forces 5 times as high as the non-neurotized controls. Indirect stimulation via the nerve elicited contractions of neurotized constructs. Curare administration ceased contraction in these constructs, providing physiologic evidence of NMJ formation. Histology demonstrated intact muscle fibers, and immunostaining positively identified NMJs. These results indicate that neurotization of engineered skeletal muscle significantly increases force generation and causes NMJs to develop, allowing indirect muscle stimulation.
工程化功能性骨骼肌在重建手术中会大有裨益。我们之前的工作成功地在体内生成了三维血管化骨骼肌。由于神经信号引导肌肉成熟，我们推测对这些构建体进行神经化会增加其收缩力。此外，如果神经肌肉接头（NMJ）得以发育，那么间接刺激（通过神经）将成为可能，从而实现定向控制。培养大鼠成肌细胞，将其悬浮于纤维蛋白凝胶中，并植入同基因大鼠股血管和横断的股神经周围的硅胶腔内4周。经神经化的构建体产生的收缩力是非神经化对照的5倍。通过神经进行的间接刺激引发了经神经化构建体的收缩。给予箭毒可使这些构建体停止收缩，这为NMJ形成提供了生理学证据。组织学显示肌纤维完整，免疫染色阳性鉴定出了NMJ。这些结果表明，工程化骨骼肌的神经化显著增加了力量产生，并促使NMJ发育，从而实现肌肉的间接刺激。
