Circadian variation in urinary melatonin in clinically healthy women in Japan and the United States of America.
Urinary melatonin excretion is lower in East-Asian (Japanese) than in North-American (whites of mixed ethnic origin) women. Moreover, a statistically significant circadian rhythm is demonstrated by population-mean cosinor in the data pool from both groups of women. Furthermore, statistical significance characterizes interactions of effects from geographic differences (between ethnic groups) with temporal factors. Such spatio-temporal interactions await further scrutiny with a view inter alia of carcinogenesis as it is influenced by a spectrum of intermodulating rhythms.
D000328:Adult; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D007564:Japan; D008550:Melatonin / Q000652:urine*; D008593:Menopause; D008875:Middle Aged; D013223:Statistics as Topic; D014481:United States
D008550:Melatonin