Abstract
Sex-related differences can be found in many brain disorders and psychophysiological traits, highlighting the importance to systematically understand the sex differences in brain function in humans and animal models. Despite emerging effort to address sex differences in behaviors and disease models in rodents, how brain-wide functional connectivity (FC) patterns differ between male and female rats remains largely unknown. Here, we used resting-state functional magnetic resonance imaging (rsfMRI) to investigate regional and systems-level differences between female and male rats. Our data show that female rats display stronger hypothalamus connectivity, whereas male rats exhibit more prominent striatum-related connectivity. At the global scale, female rats demonstrate stronger segregation within the cortical and subcortical systems, while male rats display more prominent cortico-subcortical interactions, particularly between the cortex and striatum. Taken together, these data provide a comprehensive framework of sex differences in resting-state connectivity patterns in the awake rat brain, and offer a reference for studies aiming to reveal sex-related FC differences in different animal models of brain disorders.
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Data Availability
Raw data and codes used in the present study can be provided upon request.
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The present study was partially supported by National Institute of Neurological Disorders and Stroke (R01NS085200). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
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The present study was supported by National Institute of Neurological Disorders and Stroke (R01NS085200).
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Q.L. and N.Z. designed the study; Q.L. collected and analysed the data; Q.L. and N.Z. wrote, edited and revised the manuscript. N.Z. obtained the funding. Both authors reviewed the manuscript.
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Li, Q., Zhang, N. Sex differences in resting-state functional networks in awake rats. Brain Struct Funct 228, 1411–1423 (2023). https://doi.org/10.1007/s00429-023-02657-4
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DOI: https://doi.org/10.1007/s00429-023-02657-4