ULTRASTRUCTURAL CHANGES IN NEURONS EXPOSED TO CHRONIC STRESS
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Abstract
Background: Chronic stress is known to induce profound alterations in neuronal structure, potentially underpinning cognitive and emotional dysfunction observed in affected individuals. Objective: This electron microscopic study aimed to characterize ultrastructural changes in neurons exposed to chronic stress.
Methodology: Twenty-five male Wistar rats were subjected to daily restraint stress for 6 weeks, followed by perfusion fixation and brain tissue processing for transmission electron microscopy (TEM). Ultra-thin sections of prefrontal cortex and hippocampus were analyzed for synaptic morphology, dendritic structure, and mitochondrial integrity using ImageJ software. Quantitative comparisons between stressed and control groups were made using appropriate statistical tests, adhering to ethical guidelines for animal research.
Results: Data were collected from 25 rats in this experimental design study. In the Elevated Plus Maze, the stressed group spent less time in the open arms (150 ± 15 seconds) compared to the control group (300 ± 20 seconds). Similarly, in the Open Field Test, the stressed group spent less time in the center (90 ± 12 seconds) than the control group (180 ± 18 seconds). Synaptic density in the prefrontal cortex was lower in the stressed group (0.55 ± 0.04 synapses/µm²) than in the control group (0.80 ± 0.05 synapses/µm²), with a p-value of <0.01. Similarly, in the hippocampus, the stressed group had reduced synaptic density (0.60 ± 0.03 synapses/µm²) compared to the control group (0.85 ± 0.04 synapses/µm²), also with a p-value of <0.01.
Conclusion: It is concluded that chronic stress induces significant ultrastructural changes in neurons, particularly in the prefrontal cortex and hippocampus.
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Aisha Sayyeda
Senior Lecturer, The University of Modern Sciences (Indus College of Physiotherapy)
Dr Qurat ul ain Khan
Assistant Professor Anatomy, Liaquat College of Medicine and Dentistry
Gulraiz Karim Rind Baloch
Assistant Professor, Department of Anatomy, Ziauddin University, Karachi, Pakistan
Dr Sarah Sughra Asghar
Assistant Professor, Department of Anatomy, Sir Syed College of Medical Sciences for Girls
Farah Malik
Assistant Professor Anatomy, Liaquat College of Medicine and Dentistry
Dr Hira Naeem
Associate Prof, Department of Pharmacology, Baqai Institute of Pharmaceutical sciences, Baqai Medical University.
Dr Afsheen Mansoor
Associate Professor, School of Dentistry, Shaheed Zulfiqar Ali Bhutto medical University, Islamabad.
Emaan Mansoor
Islamic International Dental college, Riphah International University, Islamabad.