Assessment of the severity of delayed changes in the state of the neuromuscular system during correction of local cold injury of III-IV degree with pCMV-VEGF165 plasmid preparation in an experiment

Introduction: The relevance of the topic is due to a wide range of clinical manifestations of frostbite, including long-term complications such as neuropathy, chronic pain, and functional impairments. Tissue recovery after frostbite depends on the degree of microvascular damage, and VEGF (vascular endothelial growth factor) is considered a promising agent for stimulating angiogenesis and improving tissue trophism. The aim of the study was to study the effectiveness of the use of a genetic construct – pCMV-VEGF165 plasmid in the correction of delayed complications of cold injury in rats. Materials and Methods: Local frostbite of III-IV degree was modeled in 18 rats using a neodymium magnet cooled in liquid nitrogen. On days 2 and 7 after the injury, pCMV-VEGF165 (60 µg) was administered to the wound edges. The control group received a placebo. The state of the neuromuscular system was assessed using electromyography on days 28 and 60. Results and Discussion: In the control group, a significant decrease in the amplitude of the M-response (1.75 times, p=0.001) and an increase in the latency period by 10% (p=0.004) were observed, indicating axonal damage and myelinopathy. The decrement index of the M-response increased (2.2 times), suggesting impaired neuromuscular conduction. In the pCMV-VEGF165 group, the amplitude of the M-response, latency period, and decrement index did not differ significantly from those in the intact animal group. Conclusion: pCMV-VEGF165 promotes a reduction in the degree of tissue damage and accelerates their regeneration by restoring blood flow, confirming its effectiveness in preventing delayed complications of cold injury.