Food-entrained oscillator

Mood and hedonic value associated with feeding, food intake, foraging, consummatory behaviors, and craving in addiction complex regulation by food entrainable oscillators in the brain and periphery, neuropeptides (including orexins) and biogenic amines. 

FAA, first described by Richter (1922), is the bout of heightened locomotor activity that precedes a daily timed meal. The literature has recently been reviewed by Stephan and therefore we will not give a detailed account here (Stephan 2001, 2002). It should be emphasized, however, that this phenomenon has been demonstrated in a wide variety of species and is likely to be an important tool used by animals to restrict their foraging behaviour to a time-domain that is both safe and productive. It should also be emphasized that the food-entrained oscillator (FEO) has so far eluded structural identification. 

Davidson AJ, Poole A, Yamazaki S, Menaker M 2003 Is the food-entrainable oscillator in the digestive system Genes Brain Behav 2 1—8... 

Stephan FK 2001 Food entrainable oscillators in mammals. In Turek TJFW, Moore RY (eds) Handbook of behavioral neurobiology 12. Circadian clocks. Kluwer Academic/Plenum Publishers, New York, p 223-241... 

Menaker It is a unique interpretation for the food-entrainable oscillator. It has to be extra-SCN, because it persists with SCN-lesioned animals. It is not a unique interpretation of the enucleation experiments. 

Dunlap At the superficial level the food-entrainable oscillator looks sort of like eitgedachtnis in bees (Renner 1960). They can be trained to feed at a certain time and... 

Mieda, M., Williams, S. C., Sinton, C. M. et al. (2004a). Orexin neurons function in an efferent pathway of a food-entrainable circadian oscillator in eliciting food-anticipatory activity and wakefulness. J. Neurosci. 24, 10493-501. 

Okamura Shibata s group shows that SCN-lesioned animals are food entrainable, and CLOCK in the liver is oscillating (Kara et al 2001). 

Kosbash Let s separate the two and focus on the food-entrainable activity. You have an SCN-lesioned animal from the outset — that is an animal with a very early SCN lesion — and then you end up setting up oscillations by virtue of this restricted feeding. These are the only locomotor activity rhythms that one sees in that lesioned animal, because the normal activity wouldn t be there because the SCN isn t there. Is that correct ... 

Sassone-Corsi We have done food entrainment, but not on the Perl knockouts. The implant shows food entrainment, and thereby functions as a bomfide peripheral oscillator. 

Menaker Ralph Mistlberger has seen the same thing in SCN intact animals, which are free running in constant darkness and which are at the same time entrained to food anticipation. You can entrain them to 24 h and they will free run at 24.5 h, and these cross as if the oscillator is completely independent of the SCN. 

M-enaker I have a suggestion for an experiment. If this is a specific SCN output factor which regulates locomotion, and if there are extra-SCN oscillators that control food anticipatory activity (FAA), it ought to be possible to entrain these animals to restricted food during the time when your compound is blocking locomotor activity. They should still anticipate a food restriction with locomotor activity. 

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