Decreased melatonin synthesis in patients with coronary artery disease.
OBJECTIVE
Decreased night-time plasma levels of melatonin were recently reported in patients with coronary artery disease, and it was postulated that melatonin production may be impaired, due to a lack of synthesizing enzymes. However, since artefacts possibly influencing the release pattern were not taken into account, this interpretation was strongly criticized. We therefore carefully investigated night-time melatonin production in patients with coronary artery disease using an appropriate experimental approach. Furthermore, we examined the effect of beta-blockers, a frequently used drug in coronary artery disease therapy.


RESULTS
Forty-eight male patients with angiographically documented severe coronary artery disease, 24 of them taking beta-blockers daily in therapeutic dosages, were included. Eighteen age-matched men, with no evidence of coronary sclerosis, served as controls. To determine melatonin production, 6-sulfatoxymelatonin (aMT6s) was measured radioimmunologically from overnight urine. Urinary aMT6s concentration was significantly decreased in patients, and beta-blocker treatment did not further suppress melatonin production.


CONCLUSIONS
The data obtained using this investigative approach provide clearcut evidence that melatonin production in patients with coronary artery disease is decreased. Whether a decreased melatonin level may be a predisposing factor for coronary artery disease, or whether the occurrence of coronary artery disease decreases melatonin synthesis remains to be determined.
Sakotnik
A
A
II Medical Department, General Hospital Wels, Wels.
Liebmann
P M
PM
Stoschitzky
K
K
Lercher
P
P
Schauenstein
K
K
Klein
W
W
Eber
B
B
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D016022:Case-Control Studies; D002940:Circadian Rhythm; D003324:Coronary Artery Disease / Q000188:drug therapy / Q000378:metabolism*; D006801:Humans; D008297:Male; D008550:Melatonin / Q000031:analogs & derivatives / Q000096:biosynthesis* / Q000652:urine; D008875:Middle Aged
D000319:Adrenergic beta-Antagonists; C054513:6-sulfatoxymelatonin; D008550:Melatonin