Melatonin rhythms in Arctic urban residents

K. ‐A Stokkan, R. J. Reiter

Research output: Contribution to journalArticlepeer-review

65 Scopus citations

Abstract

Stokkan K‐A, Reiter RJ. Melatonin rhythms in Arctic urban residents. J. Pineal Res. 1994: 16: 33–36. The 24‐hr rhythm of salivary melatonin was measured in persons living in the city of Tromsø (70°N) at the following times of the year: in January at a day length of 2 hr of twilight, in June under continuous sunshine, and in March and September at about 12 hr light and 12 hr darkness. The hormone patterns varied widely between individuals, but, in general, they were consistent within most individuals between the seasons. Highest peak values occurred in January when the mean level was also significantly higher than at any other time of year. The lowest mean levels occurred in June. Although individual rhythms were not always apparent, the mean patterns showed significantly elevated melatonin concentrations during the night at all seasons. The June melatonin peak was similar to that in March and September, but appeared to be phase‐delayed with increased melatonin concentrations from midnight until 0900. It is assumed that the delayed melatonin peak in June may be associated with a tendency among people to shift their activity/rest rhythm and that the pineal sensitivity to light is reduced in the morning in summer.

Original languageEnglish (US)
Pages (from-to)33-36
Number of pages4
JournalJournal of pineal research
Volume16
Issue number1
DOIs
StatePublished - Jan 1994

Keywords

  • Saliva
  • arctic
  • human
  • melatonin

ASJC Scopus subject areas

  • Endocrinology

Fingerprint Dive into the research topics of 'Melatonin rhythms in Arctic urban residents'. Together they form a unique fingerprint.

Cite this