Updated project metadata. We investigated the relative quantification of proteins in hippocampal cytosolic and nonsynaptic mitochondrial (NSM) fractions of rats exposed to chronic social isolation (CSIS), an animal model of depression, comparing CSIS-resilient with CSIS-sensitive or control rats, via a comparative subproteomic study. Our aim was to characterize the subproteome changes representing potential long-term changes in protein expression underlying the aforementioned conditions.