The comparison of the effects of local cooling and heating on apoptosis and pyroptosis of early‐stage pressure ulcers in rats

The exploration of an effective method for preventing and treating pressure ulcers (PUs) is a hot topic in medical research. Recently, disputes about the choice of heat and cold therapies have emerged for the prevention and treatment of clinical PUs. The present study was designed to compare the effect of cool and heat therapies on pyroptosis and apoptosis of early‐stage PUs in rats. Sixty SD rats of SPF grade were randomly divided into the sham group, model group, heating group, and cooling group. We established a rat model of early‐stage PUs by using an ischemia‐reperfusion method. At the end of the experiment, the tissue underneath the compressed region was collected for hematoxylin and eosin staining, transmission electron microscopy, immunohistochemistry, immunofluorescence staining, a TdT‐mediated dUTP nick‐end labeling assay, a Western blot analysis, and a mitochondrial swelling experiment. Our results suggested that the mitochondrial apoptotic pathway and pyroptosis were involved in the formation of early‐stage PUs, and local heating increased the PU injury in rats, while local cooling reduced the PU injury in rats. This study showed that heat therapy might not be suitable for the clinical treatment and care of early‐stage PUs, while cold therapy may be more appropriate. This study showed that heat therapy might not be suitable for the clinical treatment and care of early‐stage pressure ulcers, while cold therapy may be more appropriate.