Melatonin increases NMDA receptor subunits 2A and 2B concentrations in rat hippocampus

Abstract

We investigated that the effects of melatonin on N-methyl-D: -aspartat receptor (NMDAR) subunits 2A and 2B concentrations and on markers of oxidative stress in hippocampus of rats treated with melatonin for 4 weeks. Animals were divided into four groups according to their melatonin doses (control group (C), n = 7; 5 mg/kg group (M5), n = 7; 10 mg/kg group (M10), n = 8; 20 mg/kg group (M20), n = 8) and received the melatonin as intraperitoneal injection. After 4 weeks of treatment, electrophoretic examination was done using sodium dodecyl sulfate/polyacrilamide gel electrophoresis (SDS-PAGE) and Western blotting in hippocampal homogenates of different groups. Malondialdehyde (MDA), an end product of lipid peroxidation, was assayed in all groups. There were significant increases in both NMDAR 2A; 5 mg/kg group (n = 3, p < 0.05), 10 mg/kg group (n = 3, p < 0.05), 20 mg/kg group (n = 3, p < 0.05) and NMDAR 2B expressions; 5 mg group (n = 3, p < 0.05), 10 mg group (n = 3, p < 0.05), 20 mg group (n = 3, p < 0.05), compared to the control group. No significant difference in MDA concentrations was found between groups. The present study clearly demonstrates that melatonin alters hippocampal NMDAR subunit concentrations in a dose-dependent manner without causing lipid peroxidation.

Chronic melatonin treatment rescues electrophysiological and neuromorphological deficits in a mouse model ofDown syndrome

“…In agreement with previous evidence [13][14][15], the present study showed that LTP was reduced in TS mice, and melatonin treatment for 5-6 months completely rescued LTP in the CA1 area in trisomic animals. Consistent with these findings, chronic melatonin treatment has been shown to rescue deficits in hippocampal LTP and spatial memory after intra-hippocampal injection of Ab [30], although the acute application of melatonin directly to mouse and rat hippocampal slices inhibits LTP in the CA1 region [67][68][69].…”

Gestational Chronodisruption Impairs Hippocampal Expression of NMDA Receptor Subunits Grin1b/Grin3a and Spatial Memory in the Adult Offspring

“…There is limited evidence about the mechanisms of action of melatonin in the hippocampus; however, it has been suggested that melatonin might act as a signal gathering hippocampal function through a mechanism involving the activation of NMDA receptors [53]–[55]. Regardless of the mechanisms involved, there is compelling evidence implicating Mtnr1b (isoform 2 of melatonin receptor) in learning and memory processing.…”

Melatonin protects testes against lithium-pilocarpine-induced temporal lobe epilepsy in rats: a time course study

“…As long periods of melatonin administration were under the scope of the experience, we chose 5 and 20 mg kg −1 as the lowest and highest doses of treatment. The lack of any side effect and antioxidant property have been reported previously (Sutcu et al ., ; De Butte & Pappas, ; Hemadi et al ., ). According to several previously published research studies, we assumed both doses were specific for melatonin receptors (Oner‐Iyidogan et al ., ; Semercioz et al ., ; Sutcu et al ., ; De Butte & Pappas, ).…”