The Effect of Topical Nitroglycerin on Wound Healing in Rabbits using Histopathological Investigation

Introduction: Nitroglycerin can increase the Cycle Guanosine Mono Phosphate level, enhance nitric oxide rate in tissues dilate vessels, and intensify perfusion within tissues. The aim of the present study was to conduct a microscopic investigation addressing the effect of topical 2% Nitroglycerin ointment on wound healing in rabbits. Materials and methods: Six adult male New Zealand white rabbits, weighing approximately 2.25 kg were used. Two wounds were created on each side of the spinal column. The wounds reached the deep fascia and their dimensions were 15 15 mm. The left wound was used as the control and the right wound was used as the experimental one. Immediately after the creation of wounds, a layer of nitroglycerin 2% with 1 mm thickness was put on the experimental wound daily for seven days. On days 3, 5, 7, and 14 after cutting, both the experimental and control wounds with a margin of healthy tissues were taken for the histopathological examination. Results: The distance of the two edges on the wound in treated wounds reached a significant difference, compared with control wounds on day 14. The number of inflammatory cells (with neutrophils format) in the treatment group was significantly less than those of the control group starting from day 5. In addition, the fibrin clot diameter in the treatment group was significantly less than the control group on days 5, 7, and 14. At the beginning of the experiment angiogenesis in the control group was more than in the treatment group, but it was the same in both groups on day 7, and angiogenesis in the treatment group was more than in the control group after day 7. The volume of granulation in the treatment group was more than control group and there was a significant difference on days 5, 7, and 14. Epithelial tissues diameter was higher in the treatment group and the difference became significant on day 14. Conclusion: In conclusion, the findings indicated a promising function of topical NTG in wound healing of anal fissures, tendinopathies, CNH, diabetic foot, or skin flap necrosis.