id_788. EFFECTS OF PHARMACOLOGICALLY INDUCED CHRONIC AND ACUTE STRESS ON RAT BEHAVIOR IN THE OPEN-FIELD TEST: TOWARD A NOVEL RODENT MODEL OF PTSD
Klaudia Pszczółkowska1,,2, Bartosz Caban1, Renata Bocian1, Tomasz Kowalczyk1
1 University of Lodz, Faculty of Biology and Environmental Protection, Department of Neurobiology, 141/143 Pomorska Street, 90-236 Lodz, Poland
2 University of Lodz Doctoral School of Exact and Natural Sciences, 21/23 Jana Matejki Street, 90-237 Lodz, Poland
INTRODUCTION: Stress is a common physiological response involving complex interactions between neurobiological and endocrinological factors. Numerous studies show that stress has a major contribution to the pathogenesis of multiple central nervous system dysfunctions, including post-traumatic disorder (PTSD), major depression disorder, or anxiety disorders. To provide better insight into the mechanisms underlying these diseases, rodent-based models are widely used to study the stress response. In this study, we introduce a pharmacologically induced stress model to assess PTSD-related behavioral markers using the open field test in parallel with wireless EEG recordings from the posterior hypothalamic area (PHa).
AIM(S): This study investigates the effects of corticosterone-induced chronic stress and combined chronic–acute stress on behavioral markers in a rodent model of PTSD.
METHOD(S): Sixteen male Wistar rats were divided into experimental (n = 8) and control (n = 8) groups. Rats from the experimental group were receiving constant doses of corticosterone for 21 days and were exposed to the open field test (OF) nine times. During OF testing, behavioral activity and bioelectrical signals from PHa were recorded continuously. Here, we report a subset of the behavioral analysis.
RESULTS: Behavioral analysis focused on established rodent PTSD markers, including locomotor activity, immobility, rearing, sniffing, grooming, and time spent in the center of the arena. Rats exposed to chronic and combined chronic–acute stress exhibited a pronounced increase in automatic behaviors, including grooming, fur licking, and sniffing. Behavioral differences observed between the experimental and control groups are discussed.
CONCLUSIONS: The combined model of monitoring both behavioral and bioelectrical activity in stressful conditions could be a possible tool in searching for the etiology and pharmacology of behaviors considered diagnostic criteria for PTSD, defined in the Diagnostic and Statistical Manual of Mental Disorders.