Expression patterns of FABP3 and FABP7 in the cochlea of common marmosets.

OBJECTIVE: Fatty acid-binding proteins (FABPs) are intracellular lipid chaperones that regulate fatty acids and metabolism and signaling. Although Fabp3 and Fabp7 expression has been described in the rodent cochlea, detailed characterization in a primate model has not been performed. This study investigated the spatial and temporal expression patterns of FABP3 and FABP7 in the cochlea of the common marmoset. METHODS: Immunohistochemical analyses were performed on cochlear tissues obtained from embryonic and postnatal common marmosets to evaluate the distribution of FABP3 and FABP7 during development and at birth. RESULTS: FABP3 expression in the marmoset cochlea demonstrated a high degree of conservation compared with previously reported rodent patterns. In contrast, FABP7 exhibited distinct spatial and temporal expression patterns in the primate cochlea, differing from those observed in rodent models. CONCLUSION: The preserved expression of FABP3 suggests conserved metabolic roles across species, whereas the differential expression of FABP7 may reflect species-specific aspects of cochlear physiology. These findings provide insight into metabolic regulation in the primate cochlea and may inform future investigations of auditory health and disease.