Immunoblot analysis confirming iTRAQ results for select proteins found differentially expressed in the DL and VL of aging rats. Equal amounts of protein for three rats for each age group (4 months, 4M; 12 months, 12M; 18 months, 18M; and 24 months, 24M) were loaded into each lane. The DL was probed for AAT and ANXA1 and the VL was probed for ORP150, GRP78, AAT, and ANXA1. β-actin was probed to demonstrate consisting loading.