title: Effect of pinealectomy and melatonin replacement on morphological and biochemical recovery after traumatic brain injury.
abstract: Numerous studies showed that melatonin, a free radical scavenger, is neuroprotective. In this study, we investigated the effect of pinealectomy and administration of exogenous melatonin on oxidative stress and morphological changes after experimental brain injury. The animals were divided into six groups, each having 12 rats. Group 1 underwent craniotomy alone. Group 2 underwent craniotomy followed by brain trauma and received no medication. Group 3 underwent craniotomy followed by brain trauma and received melatonin. Group 4 underwent pinealectomy and craniotomy alone. Group 5 underwent pinealectomy and craniotomy followed by brain injury and received no medication. Group 6 underwent pinealectomy and craniotomy followed by brain trauma and received melatonin. Melatonin (100 mg/kg) was given intraperitoneally immediately after trauma to the rats in Groups 3 and 6. Pinealectomy caused a significant increase in the malondialdehyde (MDA), nitric oxide (NO), glutathione (GSH), and xanthine oxidase (XO) levels, and a decrease in GSH levels as compared to the control group. Trauma to pinealectomized rats causes significantly higher oxidative stress. Exogeneous melatonin administration significantly reduced MDA, XO and NO levels, increased GSH levels, and attenuated tissue lesion area. These findings suggest that reduction in endogenous melatonin after pinealectomy makes the rats more vulnerable to trauma, and exogenous melatonin administration has an important neuroprotective effect.
authors.affiliation: Inonu University, School of Medicine, Department of Neurosurgery, Turgut Ozal Medical Center, 44069 Malatya, Turkey. atesozkan@hotmail.com
authors.forename: Ozkan
authors.initials: O
authors.lastname: Ates
authors.forename: Suleyman
authors.initials: S
authors.lastname: Cayli
authors.forename: Iclal
authors.initials: I
authors.lastname: Gurses
authors.forename: Neslihan
authors.initials: N
authors.lastname: Yucel
authors.forename: Mustafa
authors.initials: M
authors.lastname: Iraz
authors.forename: Eyup
authors.initials: E
authors.lastname: Altinoz
authors.forename: Ayhan
authors.initials: A
authors.lastname: Kocak
authors.forename: Saim
authors.initials: S
authors.lastname: Yologlu
mesh_terms: D000818:Animals; D001930:Brain Injuries / Q000473:pathology / Q000534:rehabilitation; D016166:Free Radical Scavengers / Q000008:administration & dosage / Q000627:therapeutic use; D005978:Glutathione / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008550:Melatonin / Q000008:administration & dosage* / Q000627:therapeutic use; D018696:Neuroprotective Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D018384:Oxidative Stress; D010870:Pineal Gland / Q000601:surgery*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D016166:Free Radical Scavengers; D018696:Neuroprotective Agents; D008315:Malondialdehyde; D005978:Glutathione; D008550:Melatonin