Effect of Chronic Unpredictable Mild Stress on Hippocampus and Serum Markers in Rats

Abstract

Objective: Unpredictable stress is a common factor that we encounter in our daily lives. In this context, we wanted to investigate the morphological effects of a chronic unpredictable mild stress (CUMS) model on rat hippocampus and serum levels of brain derived neurotrophic factor (BDNF) and glial fibrillary acidic protein (GFAP). Materials and Methods: This study was carried out on 16 Wistar albino rat and divided into control and experiment groups. The CUMS model protocol was applied, and the morphological structures of the hippocampus were examined. The serum GFAP/BDNF levels were measured by ELISA method. Results: The mean BDNF level was 1.65 ± 0.17 ng/mL in the control group and 2.25 ± 0.29 ng/mL in the CUMS group. The mean GFAP level was 3.04 ± 0.45 ng/mL in the control group and 2.96 ± 0.58 ng/mL in the CUMS group. When the polymorph cell layer (PCL) in gyrus dentatus was examined; the mean number of cells in the control group was 20 ± 1.38 for the left PCL and 17 ± 1.35 for the right PCL. In the stress group; the mean number of cells in the polymorph cell layer of gyrus dentatus was 27 ± 2.08 cells for the left side and 23 ± 2.01 for the right side. Conclusions: As a result, morphological changes were observed in the gyrus dentatus region which has an important role in memory formation. The cells in the polymorph cell layer of gyrus dentatus underwent changes under stress.

Keywords

• Chronic stress
• hippocampus
• brain derived neurotrophic factor (BDNF)
• glial fibrillary acidic protein (GFAP)

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