Increased frequency of AMP-activated protein kinase-positive spinal motor neurons after sciatic nerve injury in a mouse model.

The role of AMP-activated protein kinase (AMPK) in the regulation of energy metabolism and the control of skeletal muscle regeneration post injury has been described previously. It remains unknown whether this metabolic sensor plays a role in the mechanism of axonal regeneration post injury. In this study, we used a sciatic nerve crushed mouse model to detect the expression of AMPK in sciatic nerve and spinal motor neurons at 1 week, 2 weeks and 3 weeks after injury by immunofluorescence staining. Electrophysiological and histopathological studies were used to confirm the nerve injury and regeneration. Our results showed that frequency of AMPK-positive spinal motor neurons was significantly higher on day 7 after sciatic nerve crush (SNC) and peaked on day 14. No expression of AMPK was detected in axons of the sciatic nerve before and after the injury. Taken together, our study suggested a possible role of AMPK in the mechanism of motor nerve regeneration after injury.