title: Neuroprotective effect of melatonin on retinal ganglion cells in rats.
abstract: To investigate the neuroprotective effect of melatonin (MT) on retinal ganglion cells (RGCs) in rats with ischemia reperfusion injury (RIR), 24 healthy SD rats were randomly divided into two groups: group A and group B. RIR model was induced in the left eyes by increasing the pressure of the anterior chamber. Group A was treated with 10 % alcohol- normal saline (1 mL/kg/d, ip), while group B was treated with 0.5 % MT (1 mL/kg/d, ip). On the basis of the time interval between the left eyes RIR and the sacrifice, rats in both group A and group B were further divided into 3 subgroups: groups A1 and B1 (days 7), groups A2 and B2 (days 14), groups A3 and B3 (days 30), with 4 rats in each subgroup. 7 day before the sacrifice, 3 % fluorogold was bilaterally injected into superior colliculi and geniculate body. The eyes were enucleated after being sacrificed, and mounting of the retina from both eyes was performed on a slide and observed under a fluorescence microscope. Four photos were taken from each of the four quadrants of the retina. The labeled-RGCs were counted by using a computerized image analyzer. The rate of the labeled-RGCs was used for statistical analysis. Our results showed that, in group A, the rate of the labeled-RGCs was (77.16 +/- 6.35) %, (65.53 +/- 7.01) %, (53.85 +/- 4.38) % on day 7, 14 and 30. In group B, the rate of the labeled-RGCs was (81. 33 +/- 9.27) %, (79.80 +/- 8.36) %, (80. 34 +/- 11.05) % on day 7, 14 and 30. In group B, which was treated with MT after RIR, the rate of labeled-RGCs was significantly higher than that of group A on day 14 and day 30 (P<0.05). It is concluded that, in the RIR rats, MT therapy could increase the survival rate of the RGCs and could rescue and restore the injured RGCs.
authors.affiliation: Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Qiongyan
authors.initials: Q
authors.lastname: Tang
authors.forename: Yizhen
authors.initials: Y
authors.lastname: Hu
authors.forename: Yang
authors.initials: Y
authors.lastname: Cao
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D005260:Female; D008550:Melatonin / Q000494:pharmacology*; D008856:Microscopy, Fluorescence; D018696:Neuroprotective Agents / Q000494:pharmacology*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000503:physiopathology; D012165:Retinal Ganglion Cells / Q000187:drug effects* / Q000473:pathology
chemical_list: D018696:Neuroprotective Agents; D008550:Melatonin