suprachiasmatic nucleus


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Related to suprachiasmatic nucleus: pineal gland

anterior hypothalamic area

the rostral portion of the hypothalamus generally located internal to the region of the optic chiasm; contains the following nuclei: anterior hypothalamic nucleus [TA] (nucleus anterior hypothalami [TA]), anterior periventricular nucleus [TA] (nucleus periventricularis ventralis [TA]), interstitial nuclei of anterior hypothalamus [TA] (nuclei interstitiales hypothalami anteriores [TA]), lateral preoptic nucleus [TA] (nucleus preopticus lateralis [TA]), medial preoptic nucleus [TA] (nucleus preopticus medialis [TA]), median preoptic nucleus [TA] (nucleus preopticus medianus [TA]), paraventricular nucleus [TA] (nucleus paraventricularis hypothalami [TA]), periventricular preoptic nucleus [TA] (nucleus preopticus periventricularis [TA]), suprachiasmatic nucleus [TA] (nucleus suprachiasmaticus [TA]), and supraoptic nucleus [TA] (nucleus supraopticus [TA]). The latter cell group consists of dorsomedial, ventromedial, and dorsolateral parts.
See also: hypothalamus.

suprachiasmatic nucleus

A small hypothalamic nucleus lying at the base of the third ventricle, directly above the optic chiasm. This nucleus generates the brain's circadian rhythm. To entrain its rhythm with the natural day-night cycle, the nucleus is innervated by optic axons via the accessory optic tract; it also receives axons from the lateral geniculate nucleus of the thalamus, and serotonergic axons from the midbrain raphe nuclei. The suprachiasmatic nucleus sends most of its axons to the paraventricular nucleus of the hypothalamus.
See also: nucleus

suprachiasmatic nucleus

anatomic nucleus which innervates the pineal gland; thought to play a part in the management of circadian rhythms.
References in periodicals archive ?
Restricted feeding uncouples circadian oscillators in peripheral tissues from the central pacemaker in the suprachiasmatic nucleus.
The suprachiasmatic nucleus entrains, but does not sustain, circadian rhythmicity in the olfactory bulb.
As with the suprachiasmatic nucleus pathway, the pacemaker circadian gene network of Drosophila is also represented and very highly conserved in corals (Fig.
The suprachiasmatic nucleus projects to posterior hypothalamic arousal systems.
Changes to the circadian rhythm are believed to cause a degeneration of the suprachiasmatic nucleus of the hypothalamus.
With endosulfan, substantial neurodegeneration was present in ventral telencephalic regions such as the entopeduncular nucleus (e; Figure 2e) plus the diencephalic suprachiasmatic nucleus (NSC; Figure 2f) and the medial part of lateral tuberal nucleus (NLTm; Figure 2g).
We cannot, from this study, determine the origins of the individual differences in the circadian pacemaker's program," wrote the authors, suggesting that individual variations in the cycles of clock genes in the suprachiasmatic nucleus might play a role.
Suprachiasmatic nucleus or nuclei (SCN): A cluster of nerve cells located in the brain region called the hypothalamus that is responsible for generating and coordinating circadian rhythmicity in mammals.
The report, titled ''Entrainment of the Circadian Clock in the Liver by Feeding,'' said the researchers aimed at investigating ''the effects of cycles of food availability on the rhythms of gene expression in the liver, lung and suprachiasmatic nucleus.
The mammalian hypothalamus contains a small cluster of neurons called the suprachiasmatic nucleus (SCN), which acts as the major internal timepiece.
Two distinct oscillators in rat suprachiasmatic nucleus in vitro.