Impaired nocturnal synthesis of melatonin in patients with cardiac syndrome X.
We investigated nocturnal secretion pattern of melatonin in patients with cardiac syndrome X and healthy subjects. The present study performed in five patients with cardiac syndrome X and in nine healthy controls. Blood samples from all subjects were collected every 2 h intervals between 22:00 and 08:00 h. Melatonin levels were measured with a radioimmunoassay kit. Patients with cardiac syndrome X secreted less nocturnal melatonin at 02:00 h than control subjects (P=0.04). Peak and Delta melatonin (peak-lowest melatonin) were found lower in patients with cardiac syndrome X (P=0.039 and P=0.028, respectively). In conclusion patients with cardiac syndrome X show a markedly decreased nocturnal melatonin synthesis. Our study provides useful information about melatonin synthesis and release in patients with cardiac syndrome X might help physicians in managing these patients.
Altun
Armagan
A
Department of Cardiology, Medical School, Trakya University, Edirne, Turkey. altun@medscape.com
Yaprak
Mevlut
M
Aktoz
Meryem
M
Vardar
Arzu
A
Betul
Ugur Altun
UA
Ozbay
Gultac
G
D000328:Adult; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D008297:Male; D008550:Melatonin / Q000096:biosynthesis* / Q000097:blood; D017566:Microvascular Angina / Q000378:metabolism*; D008875:Middle Aged; D010870:Pineal Gland / Q000378:metabolism; D013564:Sympathetic Nervous System / Q000502:physiology; D014630:Vagus Nerve / Q000502:physiology
D008550:Melatonin