Cardiac endothelium and tissue growth.

In recent years, a number of peptide and nonpeptide signalling autacoids have been implicated in the regulation of cardiac myocyte growth as well as vasculogenesis and angiogenesis, and in the function of cardiac muscle following development. In this review, we first examine the evidence for a role for specific cytokines during cardiac ontogeny, including fibroblast factors, TGFbeta, neuregulins, and gp/30-mediated signalling pathways. Evidence is also reviewed for a role for local, intracardiac generation of endothelins and angiotensins in the regulation of cardiac muscle function and adaptation to physiologic stress. The role of cardiac myocytes in regulating angiogenesis in the developed heart is then reviewed briefly. Finally, the effects of the endogenous generation of nitric oxides by the inflammatory cytokine-inducible isoform of nitric oxide synthase (iNOS or NOS2) within the heart are also reviewed.