Examination of ANP secretion-atrial specific granules and hemodynamics

Abstract

To clarify factors affecting atrial natriuretic peptide (ANP) secretion, the relationship between blood ANP level and intracardiac pressure, and that between the number of atrial specific granules (ASG) in the right atrial auricle and ANP level were investigated in 21 patients undergoing extracorporeal circulation. In the atrial loaded group, the Group TR (Tricuspid regurgitation) served as right atrial load and Group M (Mitral valve disease) as left atrial load, ANP and the number of ASG were compared with those in the control group. Accordingly, the effect of atrial load on ANP secretion and the number of ASG were investigated. Moreover, ANP and the number of ASG in the atrial myolysis group {Group A f (atrial fibrillation)} were compared with those of the sinus rhythm group to determine effect of atrio-myolysis.
The ANP level showed a positive correlation with left atrial pressure (r=0.820 p<0.01) and with left ventricular end-diastolic pressure (r=0.726 p<0.01), but no correlation with right atrial pressure nor ventricular pressure. The ANP level in Group M was significantly higher than other groups, but there was no significant difference compared with Group TR. Consequently, the left atrium and right atrium were considered to have different effects on ANP secretion.