ABSTRACT: This study analyzes the extracellular matrix (ECM) signatures of the outer (OF = capsule + subcapsular + zona glomerulosa cells) and inner fractions (IF = zona fasciculata cells) of the rat adrenal cortex, which comprise two distinct microenvironment niches. Proteomic profiles of decellularized OF and IF samples, male and female rats, identified 252 proteins, with 32 classified as ECM-component and ECM-related. Among these, 25 proteins were differentially regulated: 17 more abundant in OF, including Col1a1, Col1a2, Col6a1, Col6a2, Col6a3, Col12a1, Col14a1, Lama5, Lamb2, Lamc1, Eln, Emilin, Fbln5, Fbn1, Fbn2, Nid1, and Ltbp4, and eight more abundant in IF, including Col4a1, Col4a2, Lama2, Lama4, Lamb1, Fn1, Hspg2, and Ecm1. Eln, Tnc, and Nid2 were abundant in the female OF, while Lama2, Lam
