Sex-dependent differences in behavior responses to LPS-induced immune stress in juvenile rats
DOI:
https://doi.org/10.14748/tj8qj631Keywords:
sex differences, spatial memory, behavior, LPS, adolescent ratsAbstract
Introduction: Adolescence is a critical developmental period characterized by increased vulnerability to stress and ongoing brain maturation. Lipopolysaccharide (LPS)-induced immune activation is a widely used experimental model to study neuroinflammation and its effects on behavior and cognition.
Aim: The aim of this article is to investigate the effects of LPS-induced immune stress on behavioral and cognitive parameters in juvenile rats, with emphasis on sex-related differences.
Materials and Methods: Juvenile rats (postnatal days 26–35) of both sexes were divided into control and experimental groups. The control group received saline, while the experimental group was treated with LPS (50 µg/kg, intraperitoneally) for 9 consecutive days. Behavioral assessment included Open Field and T-maze tests, evaluating locomotor activity, anxiety-related behavior, and spatial memory. Statistical analysis was performed to assess group differences.
Results and Conclusion: LPS-induced immune stress resulted in a sex-independent significant reduction in normal weight gain. Rats of both sexes exposed to the toxins did not show changes in motor and exploratory activity compared to their respective controls. However, in the T-maze test, male rats treated with LPS showed a significant reduction in correct alternations, indicating impaired spatial memory, while females were not affected. These findings demonstrate sex-specific differences in the immune stress response and confirm adolescence as a sensitive period in which inflammatory processes can affect brain function.
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