115 Neuroendocrinology฀Letters฀ISSN฀0172–780X Copyright฀©฀2002฀Neuroendocrinology฀Letters ORIGINAL ARTICLE Effects฀of฀Melatonin฀on฀Noncardiogenic฀Pulmonary฀Edema฀ Secondary฀to฀Adnexial฀Ischemia-Reperfusion฀in฀Guinea฀Pig Husnu Celik, 1 Ahmet Ayar, 2 Niyazi Tug, 1 Mehmet Simsek, 1 Ibrahim Ozercan, 3 Gürkan Cikim 4 & Ibrahim Bildirici 5 Firat University, Faculty of Medicine, Departments of 1. Obstetrics and Gynecology, 2. Pharmacology, 3. Pathology, 4. Biochemistry, Elazig-Turkey. Hacettepe University, Faculty of Medicine, 5. Department of Obstetrics and Gynecology, Ankara-Turkey. Correspondence฀to: Dr. Ahmet AYAR Firat University, Faculty of Medicine, (Tip Fak) Department of Pharmacology, TR-23119, Elazig, Turkey. TEL: +90 424 237 00 00/6032 FAX: +90 424 237 92 38 E-MAIL: a.ayar@irat.edu.tr Submitted: September 29, 2002 Accepted: February 1, 2002 Key words: melatonin; ischemia-reperfusion; pulmonary edema; guinea pig Neuroendocrinology฀Letters฀2002;฀ 23:115–118฀฀฀฀pii:฀NEL230202A10฀฀฀฀฀฀Copyright฀©฀Neuroendocrinology฀Letters฀2002 Abstract OBJECTIVES : Pulmonary edema has been shown to occur following ischemia- reperfusion injury in a variety of organs and effects of several pharmacological agents on ischemia-reperfusion-induced damage has been investigated previ- ously. However, there are only a few studies in the literature about pulmonary injury following adnexial ischemia-reperfusion. In this study we aimed at inves- tigating pulmonary changes following adnexial ischemia-reperfusion and the effects of melatonin on noncardiogenic pulmonary edema secondary to adnexial ischemia-reperfusion. METHODS : A total of 32 Dunkin-Harley guinea pigs were randomly divided into four groups. In group I, oopherectomy was performed following adnexial tor- sion of three hours (ischemia). Adnexial torsion of three hours followed by a 3 hours detorsion period (reperfusion) and then oopherectomy was performed in remaining three groups. No therapy was given in group one and two while isotonic saline and melatonin was applied intraperitoneally in groups three and four, respectively. Serum malondialdehyde (MDA) levels of operated ovaries and lungs and polimorphonuclear leucocyte iniltration of lungs were determined. RESULTS : MDA levels in serum, ovary and lungs were higher in detorsion groups (groups II, III) than torsion group (group I) (p<0.01). Melatonin administration signiicantly decreased the polimorphonuclear leukocytes iniltration of lung parenchime and MDA levels in serum, ovaries and lungs (groups II and IV; groups III and IV; p<0.01, p<0.01). MDA levels and lung tissue PNL iniltration levels of melatonin administered detorsioned group was similar to those levels of only salphingo-oopherectomy performed group (Group I and IV, p>0.05). CONCLUSION : Pathophysiology of ischemia-reperfusion must be considered in the cases of adnexial torsion where detorsion is thought. As an antioxidant, melatonin administration might be helpfull in decreasing post-operative mor- bidity by decreasing reperfusion injury of lungs.