This study investigates the impact of epidermal growth factor (EGF) on blood vessels, specifically on the development of intussusceptive angiogenesis in cutaneous wound healing. Excisional wounds were formed on both sides of the medulla spinalis in dorsal location of the rats. The control and EGF-treated groups were divided into two groups with respect to sacrifice day: 5 d and 7 d. EGF was topically applied to the EGF-treated group once a day. The wound tissue was removed from rats, embedded in araldite and paraffin, and then examined under transmission electron and light microscopes. The ultrastructural signs of intussusceptive angiogenesis, such as intraluminal protrusion of endothelial cells and formation of the contact zone of opposite endothelial cells, were observed in the wound. Our statistical analyses, based on light microscopy observations, also confirm that EGF treatment induces intussusceptive angiogenesis. Moreover, we found that induction of EGF impact on intussusceptive angiogenesis is higher on the 7th day of treatment than on the 5th day. This implies that the duration of EGF treatment is important. This research clarifies the effects of EGF on the vessels and proves that EGF induces intussusceptive angiogenesis, being a newer model with respect to sprouting type. (C) 2013 Elsevier GmbH. All rights reserved.