Effect of sensory and motor electrical stimulation in vascular endothelial growth factor expression of muscle and skin in full-thickness wound

Vascular endothelial growth factor (VEGF) is important in improving wound healing. We evaluated the effect of sensory (direct current, 600 microamperes) and motor (monophasic current, pulse duration 300 microseconds, 100 Hz, 2.5-3.0 mA) intensities of cathodal electrical stimulation (ES) current to release VEGF in muscle and skin in the wound site. We randomly assigned 48 male Sprague-Dawley rats into one control and two experimental groups (sensory and motor ESs). A full-thickness skin incision was made on each animal's dorsal region. The experimental groups received ES for 1 h/day every other day. In the control group, no current was applied. VEGF expression was measured in muscle and skin on the third and seventh days after surgical incision. Our outcomes demonstrated that no difference was found in the VEGF levels among groups on the third day. However, on the seventh day, the skin VEGF levels in the sensory group were significantly higher than those levels of the other groups (p < 0.05). No difference was found in the muscle VEGF levels on the third and seventh days. The results showed that sensory ES increases the release of more VEGF in skin. This mechanism may be one through which a sensory type of current is more effective in promoting wound healing.