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.