Effect of opiate, general anaesthesia and surgery on plasma atrial natriuretic peptide levels in man.

1. Animal data suggest that opiates, halothane anaesthesia and activation of the sympathetic system stimulates release of atrial natriuretic peptide (ANP). To examine whether this is so in man, venous ANP levels were measured in five patients undergoing elective cholecystectomy. 2. Plasma levels of cortisol, aldosterone, norepinephrine and epinephrine increased 3-6 fold during the study. Cortisol-aldosterone relationships were close in all patients (r = 0.73-0.97), whereas plasma renin activity and aldosterone correlations were strong in only two subjects. 3. Baseline plasma ANP concentrations were within the normal range and were not altered by opiate injection, anaesthesia, or surgery. 4. Unlike experimental animals, man exhibits little or no ANP response to opiates, halothane, or surgical stimulation of the sympathetic nervous system.