Microarray Identifies Extensive Downregulation of Noncollagen Extracellular Matrix and Profibrotic Growth Factor Genes in Chronic Isolated Mitral Regurgitation in the Dog

Abstract

LV collagen loss in isolated, compensated MR is chiefly due to posttranslational processing and degradation. The downregulation of multiple noncollagen genes important in global extracellular matrix structure, coupled with decreased expression of multiple profibrotic factors, explains the failure to replace interstitial collagen in the MR heart.