plasma atrial natriuretic factor concentration increased from the inferior vena cava to the right atrium ( 76 +/- 24 to 162 +/- 37 pg/ml , p less than 0.001 ) and from the vena cava to the aorta ( 76 +/- 24 to 177 +/- 46 pg/ml , p less than 0.001 ) .
C0042458
inferior vena cava
C0042460
vena cava