64CuCl2 PET/CT imaging of mouse muscular injury induced by electroporation.

Skeletal muscle injury is common in body injuries suffered in sports and car accidents. Development of new tracers is significant for assessing muscular injury with positron emission tomography/computed tomography (PET/CT) and monitoring repair of muscle injury in response to treatment. Copper is required for wound healing and increased copper ions were detected in the soft tissue of wound in rodents and human. Based on the recent finding of increased 64Cu uptake in the traumatic brain injury, this study aimed to explore use of 64CuCl2 as a radiotracer for molecular imaging of muscular injury using PET/CT. Focally increased 64Cu uptake by the injured muscular tissue (5.4 ± 1.2% ID/g) was detected in the C57BL/6 mice with electroporation-induced skeletal muscle injury by PET/CT after intravenous injection of 64CuCl2 as a tracer, compared to low 64Cu uptake associated with muscular inflammation induced by intramuscular injection of lipopolysaccharides (0.82 ± 0.26% ID/g, P < 0.01) or physiological 64Cu uptake of the non-injured muscular tissues (0.78 ± 0.20% ID/g, P < 0.01). The findings support further investigation of 64CuCl2 as a new radiotracer for molecular imaging of skeletal muscle injury using PET/CT.