Figure 4

Expression of Ecrg4 is down-regulated in appendages of AF patients. Specimens of atrial appendage from right atrium were harvested from 5 RHD patients with persistent AF (A, labeled AF1–5 on left panel) and 5 RHD patients with SR (B, labeled SR1–5 on right panel) respectively. The specimen were fixed, microtomed, and proceeded for IHC using anti-Ecrg4 as primary antibody and goat anti-rabbit-HRP as secondary antibody per instructions in materials and methods. Representative images (with 200x magnification on the left side and 400x magnification on the right side of A and B respectively) showing a light brown staining of cardiomyocytes (low level of Ecrg4) in all 5 specimens of atrial appendages from patients with AF (A, left panel) relative to a dark brown staining of cardiomyocytes (high level of Ecrg4) in all 5 specimens of atrial appendages from patients with SR (B, right panel).