Posters
Presenting Author Academic/Professional Position
Graduate Student
Academic Level (Author 1)
Graduate Student
Academic Level (Author 2)
Graduate Student
Academic Level (Author 3)
Faculty
Discipline/Specialty (Author 3)
Neuroscience
Presentation Type
Poster
Discipline Track
Biomedical Science
Abstract Type
Research/Clinical
Abstract
Background: Disruptions of circadian rhythms, caused by factors such as environmental changes or stress, are linked to health conditions, including metabolic disorders, cardiovascular diseases, and mood disorders. Circadian rhythm disturbances are particularly relevant for understanding the etiology of conditions like insomnia, depression, and anxiety. The circadian rhythm, primarily regulated by the suprachiasmatic nuclei (SCN) in the hypothalamus, coordinates biological processes to align with daily environmental cycles. Acute stress, especially when experienced immediately upon waking, has been shown to disrupt these rhythms, impair sleep regulation, and exacerbate mood dysregulation. Given the significant clinical implications, understanding how stress impacts circadian rhythms is crucial for developing targeted therapeutic interventions. This study uses the Syrian hamster (Mesocricetus auratus) model to explore the effects of acute stress on circadian rhythms, aiming to identify mechanisms that could inform clinical interventions for mood and sleep disorders in humans.
Methods: The study used 4 Syrian hamsters housed in a controlled environment with a 14:10 h light/dark cycle (with lights off at 11:00 AM). Each hamster underwent both control and treatment conditions in a within-subjects design. Acute stress was induced by exposing subjects to restraint for 30 minutes starting at 10:30 AM, followed by placement in an apparatus with a photobeam array system starting at 11:00 AM. The photobeam system tracked counts; number of transitions from an inactive to an active state based on movement within the cage. Additionally, the system recorded bouts, defined as periods of continuous movement. The system also measured the total active time, which represented the sum of all periods in which the hamster was moving. Data were collected during a 2-hour post-stress period. BORIS software was used to quantify specific behaviors such as grooming, freezing, and locomotion during restraint. Behavioral analysis was complemented by assessing inter-rater reliability through Cohen’s Kappa Coefficient. Repeated measures ANOVA tests were used for statistical analysis to compare activity levels between control and treatment conditions
Results: Although the differences between control and treatment conditions were not statistically significant, some trends were observed. The treatment group showed a slight tendency toward increased activity in terms of disruption of bouts, counts, and total active time. Additionally, a decrease in locomotor activity was noted at the beginning of the second hour in the treatment group, which may reflect time-dependent changes in behavior.
Conclusions: This study aims to clarify the impact of acute stress on behaviors that are regulated by circadian rhythms in hamsters. By modeling stress exposure and observing its effects on sleep-wake cycles and behavior, the findings could provide critical insights into the pathophysiology of stress-related disorders. Limitations of the study include the small sample size and translation to the human condition. Understanding these mechanisms may inform the development of clinical interventions for managing circadian rhythm disturbances in patients with anxiety, depression, and sleep disorders. Through translational research, these animal model findings could be adapted to improve treatment strategies for enhancing both mental health and overall well-being.
Recommended Citation
Villarreal, Raquel A.; Garcia, Laura E.; and Gil, Mario, "Impact of Acute Stress on Circadian Rhythm Regulation of Locomotor Activity in Syrian Hamsters" (2025). Research Symposium. 132.
https://scholarworks.utrgv.edu/somrs/2025/posters/132
Included in
Animal Experimentation and Research Commons, Behavioral Neurobiology Commons, Behavior and Behavior Mechanisms Commons, Experimental Analysis of Behavior Commons, Mental and Social Health Commons
Impact of Acute Stress on Circadian Rhythm Regulation of Locomotor Activity in Syrian Hamsters
Background: Disruptions of circadian rhythms, caused by factors such as environmental changes or stress, are linked to health conditions, including metabolic disorders, cardiovascular diseases, and mood disorders. Circadian rhythm disturbances are particularly relevant for understanding the etiology of conditions like insomnia, depression, and anxiety. The circadian rhythm, primarily regulated by the suprachiasmatic nuclei (SCN) in the hypothalamus, coordinates biological processes to align with daily environmental cycles. Acute stress, especially when experienced immediately upon waking, has been shown to disrupt these rhythms, impair sleep regulation, and exacerbate mood dysregulation. Given the significant clinical implications, understanding how stress impacts circadian rhythms is crucial for developing targeted therapeutic interventions. This study uses the Syrian hamster (Mesocricetus auratus) model to explore the effects of acute stress on circadian rhythms, aiming to identify mechanisms that could inform clinical interventions for mood and sleep disorders in humans.
Methods: The study used 4 Syrian hamsters housed in a controlled environment with a 14:10 h light/dark cycle (with lights off at 11:00 AM). Each hamster underwent both control and treatment conditions in a within-subjects design. Acute stress was induced by exposing subjects to restraint for 30 minutes starting at 10:30 AM, followed by placement in an apparatus with a photobeam array system starting at 11:00 AM. The photobeam system tracked counts; number of transitions from an inactive to an active state based on movement within the cage. Additionally, the system recorded bouts, defined as periods of continuous movement. The system also measured the total active time, which represented the sum of all periods in which the hamster was moving. Data were collected during a 2-hour post-stress period. BORIS software was used to quantify specific behaviors such as grooming, freezing, and locomotion during restraint. Behavioral analysis was complemented by assessing inter-rater reliability through Cohen’s Kappa Coefficient. Repeated measures ANOVA tests were used for statistical analysis to compare activity levels between control and treatment conditions
Results: Although the differences between control and treatment conditions were not statistically significant, some trends were observed. The treatment group showed a slight tendency toward increased activity in terms of disruption of bouts, counts, and total active time. Additionally, a decrease in locomotor activity was noted at the beginning of the second hour in the treatment group, which may reflect time-dependent changes in behavior.
Conclusions: This study aims to clarify the impact of acute stress on behaviors that are regulated by circadian rhythms in hamsters. By modeling stress exposure and observing its effects on sleep-wake cycles and behavior, the findings could provide critical insights into the pathophysiology of stress-related disorders. Limitations of the study include the small sample size and translation to the human condition. Understanding these mechanisms may inform the development of clinical interventions for managing circadian rhythm disturbances in patients with anxiety, depression, and sleep disorders. Through translational research, these animal model findings could be adapted to improve treatment strategies for enhancing both mental health and overall well-being.
