Adrenomedullin (AM), a novel vasodilatory peptide, appears to participate i
n the regulation of circulation. Recent studies have reported a relationshi
p between AM and cytokine. The present study was performed to determine whe
ther major surgery, which is accompanied by an altered cytokine production,
affects the concentration of plasma AM. Eighteen patients undergoing major
upper abdominal and thoracoabdominal surgery were thus studied. Arterial b
lood samples were obtained before anesthetic induction (PRE), 2h after a su
rgical incision was made (2H), at the end of surgery (END), at postoperativ
e day 1 (1POD), and at 3POD. The concentrations of plasma AM and serum inte
rleukin (IL)-6 were measured. The levels of plasma AM were found to be sign
ificantly higher at END (P < 0.001), 1POD (P < 0.0001), and 3POD (P < 0.05)
compared with PRE. A significant correlation was found between the concent
rations of serum IL-6 and plasma AM (r = 0.59, n = 18, P < 0.01). These res
ults suggest that major surgical stress might thus increase the plasma AM c
oncentration, and such an increase may be related to cytokine induction.