Myocardial fibroblasts of rat are an important source of producing adrenomedullin / 中国病理生理杂志

ABSTRACT

AIM: To elucidate the cellular source of adrenomedullin (AM) in myocardial tissue, the effects of 5 substances on secretion of AM from cultured rat fibroblasts and myocytes were examined in this study. METHODS: Myocardial fibroblast and myocyte isolation and culture; AM was measured by radioimmunoassay; AM receptors were assayed by radioactive analysis method. RESULTS:Tumor necrosis factor ? (TNF?), lipopolysaccharide (LPS) and basic fibroblast growth factor (bFGF) all could stimulate AM synthesis and secretion in myocardial Fb and myocyte , and the amount of AM secreted by Fb was greater than that by myocytes, whereas transforming growth factor-?(TGF?),and interferon-?(IFN?) suppressed in it in myocardial Fb and myocytes. Myocardial Fb has two kinds of AM binding sites, but myocyte has only one high affinity- binding site.CONCLUSIOIN:Myocardial fibroblasts could synthesize and secrete AM, and there are AM receptors in both myocardial fibroblasts and myocytes.