Open AccessAtriopeptin III induces early relaxation of isolated mammalian papillary muscle.
Author(s) -
Ann Meulemans,
Karin Sipido,
Stanislas U. Sys,
Dirk L. Brutsaert
Publication year - 1988
Publication title -
circulation research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.899
H-Index - 336
eISSN - 1524-4571
pISSN - 0009-7330
DOI - 10.1161/01.res.62.6.1171
Subject(s) - sodium nitroprusside , medicine , papillary muscle , endocrinology , natriuresis , vasodilation , isometric exercise , atrial natriuretic peptide , isotonic , chemistry , cardiac muscle , volume overload , nitric oxide , heart failure , kidney
Atrial natriuretic peptide, released by mammalian atria in response to volume overload, induces vasodilation and natriuresis. In this study, a direct effect on cardiac mechanical performance was demonstrated. Atriopeptin III (10(-9)-10(-7) M) induced early relaxation and decreased peak twitch of isometric and isotonic twitches of isolated papillary muscles of cat and rat, without affecting maximal unloaded velocity of shortening. This effect resembled the effects of dibutyryl cyclic GMP and of sodium nitroprusside on cardiac muscle. The action of atriopeptin III, but not of dibutyryl cyclic GMP or sodium nitroprusside, was abolished by mechanically or chemically damaging the endocardial endothelial surface. Thus, the early relaxation of cardiac muscle induced by atrial natriuretic peptide may be mediated through receptors on the endocardial endothelium.