Melatonin Modulates NMDA-Receptor 2B/Calpain-1/ Caspase-12 Pathways in Rat Brain After Long Time Exposure to GSM Radiation

Özet

AIM: To investigate the potential protective effects of melatonin on the chronic radiation emitted by third generation mobile phoneson the brain.MATERIAL and METHODS: A total of 24 male Wistar albino rats were divided into four equal groups. Throughout a 90-dayexperiment, no application was performed on the control group. The second group was exposed to 2100 MHz radiation for 30minutes. Subcutaneous melatonin was injected into the third group. Subcutaneous melatonin injection was applied 40 minutesbefore radiation and then the fourth group was exposed to radiation for 30 minutes. At the end of the experiment, brain (cerebrumand cerebellum) tissues were taken from the subjects. Histochemical, immunohistochemical, ultrastructural and western blotanalyses were applied. In addition to brain weight, Purkinje cells’ number, immunohistochemical H Score analyses and the resultsof the Western blot were examined statistically.RESULTS: With the application of radiation, neuronal edema, relatively-decreased numbers of neurons on hippocampal CA1 andCA3 regions, displacement of the Purkinje neurons and dark neurons findings were observed as a result of histochemical stainings.Radiation also activated the NMDA-receptor 2B/Calpain-1/Caspase-12 pathway, NMDA-receptor 2B and Calpain-1 with the findingsbeing supported by western blot analyses. Pre-increased protein synthesis before apoptosis was identified by electron microscopy.CONCLUSION: Mobile phone radiation caused certain (ultra) structural changes on the brain and activated the NMDA-receptor 2B/Calpain-1/Caspase-12 pathway; in addition, melatonin was found to be effective, but insufficient in demonstrating the protectiveeffects.