Updated project metadata. Different sites and changes in the tissue microenvironment have been associated with the cortex of adrenal gland functionality, maintenance, and renewal. Here we describe the differences between the extracellular matrix (ECM) signatures of the outer (OF) and inner fractions (IF) of the rat adrenal cortex. We compared the proteomic profiles of decellularized OF and IF rat adrenal samples followed by the analysis of the proteomic profiles of male and female samples. Our analysis of OF and IF samples simultaneously showed a total of 186 proteins, 69 proteins were identified in OF and 144 in IF. Ninety-two proteins were in common to both fractions, 5 proteins were exclusive to OF, and 89 proteins were exclusive to IF. A total of 42 proteins were assigned as ECM, 13 as structural ECM constituents, 17 as ECM components, and 12 as related to functional processes in ECM. Col14a1, Fbn2, and Ltbp4 were exclusive to and upregulated in the OF while Gpt2, Chga, Chgb, and Plg were exclusive to and upregulated in the IF. In addition, Nid2 and Lama2, both ECM components, were identified as upregulated in female OF and male IF adrenal, respectively. Next, we validated the main findings by using qPCR, histochemistry, and immunohistochemistry approaches.