Glucocorticoids change the transcript levels of galanin, galanin receptor-2 and brain-derived neurotrophic factor in rat hippocampal neurons

Glucocorticoids (GCs) can affect hippocampal structure and function in animals and humans. This study was designed to investigate the possible functional molecules and mechanisms involved in the action of GCs on hippocampal neurons. Rat primary hippocampal neurons were cultured and treated with glucocorticoids at a low concentration (LC, 10⁻⁸ mol/L), a middle concentration(MC, 10⁻⁷ mol/L) and ahigh concentration (HC, 10⁻⁶ mol/L). Theresults indicate that GCs do not change the viability of hippocampal neurons but do change the catalase (CAT) activity and malondialdehyde (MDA) content. The transcription expression levels of brain derived neurotrophic factor (BDNF), galanin (GAL), galanin receptor-2 (GALR2) and neuropeptide Y receptor-5 (NPYR5) genes in the HC group were significantly higher than those in the control group (p<0.05). These results suggest that hippocampal neurons launch the neuron protection pathways mediated by GAL, GALR2 and BDNF molecules when encountering an experimentally high concentration of corticosteroids.