Localization of immunoreactive synthetic atrial natriuretic factor (ANF) in the heart of various animal species.

Abstract

The localization of two synthetic fragments of the C-ter-'Supported by a Medical Research Council ofCanada Group Grant to the Multidisciplinary Research Group on Hypertension.

Mr-Proanp Rises during Exercise Even after Surgical Closure of the Left Atrial Appendage: A Sub-Study of the Laacs Randomized Study

“…Even though LAA is thought to play a central role in MR-proANP release, [7,8] studies using immunohistochemically techniques have demonstrated a greater number of intensely granulated cardiomyocytes secreting MR-proANP in the right rather than in the left atrium [9]. If the myocytes outside the LAA produce most of the MR-proANP, it can be difficult to measure the impact of LAA closure on MR-proANP levels, thereby explaining our results.…”

“…It is important to notice that the right atrial appendage in our cohort has been left untreated, furthermore supporting that the right atrial appendage is an area of importance involved in ANP production. Studies using immunohistochemically techniques have also demonstrated a greater number of intensely granulated cardiomyocytes secreting MR-proANP in the right rather than in the left atrium [9].…”

“…Therefore resting levels of natriuretic peptides are higher in chronic heart failure and atrial fibrillation compared with normal [1,11,12]. ANP gene transcripts have been shown in both atrial and ventricular myocytes; however, the level of ventricular ANP transcription is generally lower than that found in the atria [1,9,13].…”

“…It increases glomerular filtration and decreases renin secretion, countereffecting the renin-angiotensin-aldosterone system, thereby acting as a diuretic [2,5,6] In addition, ANP has a cardio protective role by regulating cellular growth, cellular proliferation, and cardiac hypertrophy [7]. Under normal circumstances the myocytes in the atria and the ventricles in the human heart will produce ANP to regulate fluid homeostasis [8,9] but when the ventricles and atria in the heart are stretched, the synthesis of these peptides increases. ANP gene expression is increased in the ventricular myocardium of the failing heart proportionally with the severity of congestive heart failure or ventricular haemodynamic overload [10].…”

The Left Atrial Appendage in Health and Disease

“…These afferent signals play a role in fluid haemostasis and control of heart rate in response to changes in LA pressure. In support of this, one study demonstrated that 30% of all cardiac atrial natriuretic peptide (ANP) was found within the LAA [9]. Furthermore in the healthy human heart, ANP concentration in the LAA is present in 40-times the concentration of the rest of the LA [10].…”