Visual EMDR stimulation mitigates acute varied stress effects on morphology of hippocampal neurons in male Wistar rats

Abstract

Introduction: Stress is a pervasive health concern known to induce physiological changes, particularly impacting the vulnerable hippocampus and the morphological integrity of its main residing cells, the hippocampal neurons. Eye Movement Desensitization and Reprocessing (EMDR), initially developed to alleviate emotional distress, has emerged as a potential therapeutic/preventive intervention for other stress-related disorders. This study aimed to investigate the impact of Acute Variable Stress (AVS) on hippocampal neurons and the potential protective effects of EMDR.

Methods: Rats were exposed to diverse stressors for 7 days, followed by dendritic morphology assessment of hippocampal neurons using Golgi-Cox staining.

Results: AVS resulted in significant dendritic atrophy, evidenced by reduced dendritic branches and length. In contrast, rats receiving EMDR treatment alongside stress exposure exhibited preserved dendritic morphology comparable to controls, suggesting EMDR's protective role against stressinduced dendritic remodeling.

Conclusions: These findings highlight the potential of EMDR as a neuroprotective intervention in mitigating stress-related hippocampal alterations.

Keywords: EMDR; Golgi-Cox; Sholl analysis; hippocampus; stress.

Figure 1

This shows the main procedures of the experiments carried out. Control group (CONTROL), Variable Stress (AVS), Eye Movement Desensitization and Reprocessing group + Acute Variable Stress (EMDR + AVS), and an Eye Movement Desensitization and Reprocessing group (EMDR).

Figure 2

Schematic representation of neuronal dendritic morphology. (A) Control group; (B) Eye Movement Desensitization and Reprocessing group (EMDR); (C) Acute Variable Stress group (AVS); (D) Acute Variable Stress group + Eye Movement Desensitization and Reprocessing group (AVS +EMDR); (E) Sholl analysis; (F) Panoramic microscopy photograph of the hippocampus stained with Golgi-cox; (G) Representative microscopic photograph 20X (1296×972, 0.22 px/μm) of Golgi-cox staining.

Figure 3

Morphometry of hippocampal neurons. Illustrates the Sholl analysis with the number of intersections found in 50 neurons per group. Control group; Eye Movement Desensitization and Reprocessing group (EMDR); Acute Variable Stress group (AVS); Acute Variable Stress group + Eye Movement Desensitization and Reprocessing group (AVS +EMDR). Data represent the mean ± SEM. *p < 0.05 (**p < 0.01, ***p < 0.001).

Figure 4

Dendritic complexity in hippocampal neurons. Control group; Eye Movement Desensitization and Reprocessing group (EMDR); Acute Variable Stress group (AVS); Acute Variable Stress group + Eye Movement Desensitization and Reprocessing group (AVS +EMDR). Data represent the mean ± SEM. *p < 0.05 (**p < 0.01, ***p < 0.001).

Figure 5

Length dendritic complexity in hippocampal neurons. Control group; Eye Movement Desensitization and Reprocessing group (EMDR); Acute Variable Stress group (AVS); Acute Variable Stress group + Eye Movement Desensitization and Reprocessing group (AVS +EMDR). Data represent the mean ± SEM. *p < 0.05 (**p < 0.01, ***p < 0.001).