Circadian clocks have evolved to predict and coordinate physiologic processes with the rhythmic environment on Earth. Space studies in non-human primates and humans have suggested that this clock persists in its rhythmicity in space but that its function is altered significantly in long-term space flight. Under normal circumstances, the clock is synchronized by the light-dark cycle via the retinohypothalamic tract and the suprachiasmatic nucleus. It is also entrained by restricted feeding regimes via a suprachiasmatic nucleus-independent circadian oscillator. The site of this suboscillator (or oscillators) is not known, but new evidence has suggested that peripheral tissues in the liver and viscera may express circadian clock function when forced to do so by restricted feeding schedules or other homeostatic disruptions. New research on the role of the circadian clock in the control of feeding on Earth and in space is warranted.
|Number of pages||6|
|State||Published - Oct 2002|
Bibliographical noteFunding Information:
Research in the Cassone laboratory is supported by NIH PO1 NS39546 and NASA Subcontract NSBRI CA00208 to V.M.C. Research in the Stephan laboratory is supported by NIH RO1-DK-50224 to F.K.S.
- Suprachiasmatic nucleus
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism
- Nutrition and Dietetics