THE EFFECTS OF MELATONIN ON ANGIOGENESIS AND WOUND HEALING

Abstract

The effects on angiogenesis of melatonin hormone were researched in wound healing process in the experimental study model, using 30 Wistar Albino rats. Although wound healing is not a well-known process, cells of immune system increase releasing of factors which are effective in the process. Whereas it is known that melatonin particularly induces productions of IL-1, TNF-alfa and TGF-beta. Immunomodulator effect of melatonin is unclear at the proliferation phase of wound healing. Rats were divided into two equal groups. Before and after the incisions made on the back skin, 0,9% NaCl at the dose of 0.25 cc/rat/d was injected to group l, and melatonin dissolved in 0,9% NaCl at the dose of 0,4 mg/kg/d was injected to group 2 via intramusculer route, The phases of healing were assessed as compared with the control group, At 3,7,10,14 and 21 days of the study, excisionel biopsies were made from the healing tissues, and were investigated for angiogenesis criterions under light and electron microscopes. Hydroxyprolin levels were also measured in the tissues. Unlike in control group, it was seen that neovascularization began in every stages of light and electron microscopic examinations and that there was a significant increase in the number of new vessels (p<0.05). in all stages, particularly at 10, 14 and 21 days, melatonin group showed better developing than control group in measurement of the tissue hydroxyprolin levels. Melatonin may have positive effects on angiogenesis and wound healing, and the results were encouraging new studies.