Meeting Abstract

P2.28  Tuesday, Jan. 5  Inflammation and Repair in a Goldfish (Carassius auratus) Model of Heart Injury. GRIVAS, J.A.*; GOLDEN, B.L.; FROUNTFELTER, T.; LESCH, M.A.; COBB, A.; LAFONTANT, P.J.; DePauw University; DePauw University; DePauw University; DePauw University; DePauw University; DePauw University pascallafontant@depauw.edu

Among teleosts, the zebrafish is able to regenerate its heart following resection. We studied the wound healing and repair response in the heart of goldfish following cautery injury to the ventricular myocardium. Electron microscopy and immunohistochemistry studies revealed a robust inflammatory response in the first week consisting primarily of infiltrating macrophages, heterophils, and mast cells. These inflammatory cells where identified in the lumen of spongy heart, within the site of the wound, and attached to endothelial cells adjacent to the site of injury. Inflammatory cells were also present in the compact layer of myocardium both adjacent and remote to the site of injury. PCNA-positive cells where observed in the injured area during the first three weeks. Collagen fibers accumulated at the beginning of the second week in a transition zone between healthy and injured myocardium and in adjacent subepicardial regions. By 6 weeks the injury appeared to be completely resolved. Our data suggest that effective repair mechanisms suggestive of regeneration operate in the injured goldfish heart.