Université de Fribourg

Behavioural food-anticipation in clock genes deficient mice: confirming old phenotypes, describing new phenotypes

Mendoza, Jorge ; Albrecht, Urs ; Challet, Etienne

In: Genes, Brain and Behavior, 2010, vol. 9, p. -

Animals fed daily at the same time exhibit circadian food-anticipatory activity (FAA), which has been suggested to be driven by one or several food-entrainable oscillators (FEOs). FAA is altered in mice lacking some circadian genes essential for timekeeping in the main suprachiasmatic clock (SCN). Here we confirmed that single mutations of clock genes Per1−/− and...

Université de Fribourg

Restoration of circadian rhythmicity in circadian clock-deficient mice in constant light

Abraham, Diya ; Dallmann, Robert ; Steinlechner, Stephan ; Albrecht, Urs ; Eichele, Gregor ; Oster, Henrik

In: Journal of Biological Rhythms, 2006, vol. 21(3), p. 169-176

In mammals, circadian rhythms in behavior and physiology are controlled by a central pacemaker, the SCN, and subordinated clocks throughout the body. On the molecular level, these clocks are based on transcriptional/translational feedback loops involving a set of clock genes that regulate their own transcription. Among the components driving the mammalian circadian clock are the Period 1...

Université de Fribourg

The opioid fentanyl affects light input, electrical activity and Per gene expression in the hamster suprachiasmatic nuclei

Vansteensel, Mariska J. ; Magnone, Maria Chiara ; Oosterhout, Floor van ; Baeriswyl, Stéphanie ; Albrecht, Urs ; Albus, Henk ; Dahan, Albert ; Meijer, Johanna H.

In: European Journal of Neuroscience, 2005, vol. 21(11), p. 2958

The suprachiasmatic nuclei (SCN) contain a major circadian pacemaker, which is regulated by photic and nonphotic stimuli. Although enkephalins are present in the SCN, their role in phase regulation of the pacemaker is largely unknown. The opioid agonist fentanyl, a homologue of morphine, is an addictive drug that induces phase shifts of circadian rhythms in hamsters. We observed that these phase...