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Updated: Aug 18, 2026

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
Features of the circadian clock in the avian pineal gland
V Csernus1, N Faluhelyi, A D Nagy
1Department of Anatomy, University of Pécs, Medical School, Hungary. valer.csernus@aok.pte.hu
Abstract:
The effects of different environmental factors on the circadian rhythm of melatonin release by chicken pineal glands were analyzed in 5-day experiments in vitro. Periodic, brief 4-h illumination at around midnight resulted in phase inversion in 2 days. Exposure to repeated 41 degrees C temperature elevation at around midnight caused no phase shift in the basic melatonin rhythm. Repeated inversion of the polarity of the magnetic field also affected rhythmic melatonin release. Additionally, expressions of Per1, Per2, Per3, Bmal1, Bmal2, Clock, Cry1, and Cry2 clock genes were simultaneously detected in single chicken pineal glands.
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