Intestinal Mitochondrial Dysfunction Of Neonatal Rats Underdoing Surgical Stress And The Protective Effects Of Melatonin

OBJECTIVE: To study enterocyte mitochondrial dysfunction of neonatal rats undergoing surgical stress and the protective effects of melatonin.Methods: 30 Sprague-Dawley neonatal rats were randomly divided into 5 groups: control (no operation), surgical manipulation (intestinal handling), sham control (laparotomy without intestinal handling), melatonin treated groups 1 (MT1), melatonin treated groups 2(MT2). Rats were anesthetized by diethyl ether and the abdominal wall was opened by a laterigrade incision of approximately 1cm. The intestine was then gently moved and handled simulating the"inspection"that occurs in a clinical setting . The intestine then was then replaced into the abdominal cavity. The whole process was completed within 1–2min. Animals sacrificed by decapitation at 60 min, after the surgical procedure. Enterocytes were isolated from the small intestine. Mitochindrial ultrastructure and parameters of morphology of the above groups were observed by electron microscope. Mitochondria were prepared from isolated enterocyte and the content of MDA,SOD,NO were detected.Result: Enterocyte mitochondrial MDA was obviously enhanced than control, together with the decrease of SOD and NO. Swollen mitochondria and distorted cristae were seen by electron microscope. Compared with surgical manipulation and sham control, Mitochindrial damage of parameters of morphology was obviously improved in MT1 and MT2, together with the decrease of mitochondrial MDA and the raise of SOD . But the increase of...