Background: The ionotropic glutamate receptor AMPA (AMPAR) mediates fast excitatory synaptic transmission and regulates synaptic strength in various parts of the CNS. Emotional challenges can affect these processes by influencing AMPAR levels and localization via stress hormones, resulting, e.g., in behavioral changes. AMPARs are essential for auditory processing, but their response to stress hormones in the central or peripheral auditory system remains poorly understood. Therefore, this scoping review examines the effects of corticosterone (CORT), a primary stress hormone in rodents, on AMPA receptor levels and localization in the rodent nervous system and considers potential implications for the auditory system. Methods: We systematically searched PubMed, Web of Science, and OVID EMBASE using MeSH terms related to AMPA receptors and corticosterone. Studies were screened based on predefined inclusion criteria, including original research published in English that focused on AMPA receptor subunits (e.g., GluR1-4, GluA1-4, Gria1-4). Of 288 articles screened, 17 met the criteria for final analysis. Results: No reports were found regarding CORT action in the auditory system. Three main experimental models used in the included research were identified: neuronal cultures, isolated tissue cultures, and animal models. Generally, short-term CORT exposure increases AMPAR surface localization and mobility in neuronal cultures, especially in the hippocampus and prefrontal cortex. However, results from animal models were inconsistent due to variations in experimental design and other factors. The isolated tissue study did not provide sufficient data for clear conclusions. Conclusions: Variability in experimental models limits our ability to draw definitive conclusions about the effects of CORT on AMPARs across different regions of the nervous system. The differences in live animal studies highlight the need for standardized methods and reporting. Since AMPARs play a crucial role in auditory processing, CORT-induced changes in neuronal cultures may occur in the auditory system. Further research is needed to explore the specific responses of AMPAR subunits and how stress hormones may influence auditory disorders, which could help identify potential treatment strategies.

Mineralocorticoid (MR) and glucocorticoid (GR) receptors regulate stress and inflammation pathways relevant to hearing and balance, as well as corticosteroid treatments. However, translation to clinical outcomes remains inconsistent, likely due to biologically significant species-, strain-, and tissue-specific differences in receptor distribution. We performed a scoping review to analyze the presence, cellular and subcellular localization, and regional expression of MR and GR in the mammalian inner ear. Searches of PubMed, Web of Science, and ScienceDirect without date limits identified original studies reporting MR or GR localization or expression in cochlear or vestibular tissues. Twenty-three studies met the criteria. Both receptors were found in various cochlear and vestibular regions across species, indicating widespread corticosteroid signaling in the inner ear. Nonetheless, the data were unevenly distributed, with limited human data mainly focusing on GR, while MR was less characterized, especially in vestibular tissues and in humans. GR localization varied across strains and developmental stages, particularly in rodents, and methodological heterogeneity complicated cross-study comparisons. Overall, the literature suggests a broadly conserved yet incomplete map of corticosteroid receptor distribution in the mammalian inner ear, which affects model choice and the interpretation of translational steroid studies.