A physiological model of a circannual oscillator

Duncan J. MacGregor, Gerald A. Lincoln

Research output: Contribution to journalArticlepeer-review

Abstract / Description of output

Recent evidence based on studies in hypothalamo-pituitary disconnected Soay sheep suggests that the generation of circannual rhythms may be localizable to specific tissues or physiological systems. Now, the authors present a physiological model of a circannual rhythm generator centered in the pituitary gland based on the interaction between melatonin-responsive cells in the pars tuberalis that act to decode photoperiod, and lactotroph cells of the adjacent pars distalis that secrete prolactin. The model produces a self-sustained, circannual rhythm in endocrine output that the authors explore by mathematical modeling. The circannual oscillation requires a delayed negative feedback mechanism. The authors highlight specific features of the pituitary dynamics as a guide to future research on circannual rhythms.

Original languageEnglish
Pages (from-to)252-264
Number of pages13
JournalJournal of biological rhythms
Issue number3
Publication statusPublished - Jun 2008


Dive into the research topics of 'A physiological model of a circannual oscillator'. Together they form a unique fingerprint.

Cite this