Disease relevance of Suprachiasmatic Nucleus

• Melanopsin ganglion cells convey information regarding general levels of environmental illumination to the suprachiasmatic nucleus, the intergeniculate leaflet, and the pretectum [1].
• Effect of infusion of vasoactive intestinal peptide (VIP)-antisense oligodeoxynucleotide into the third cerebral ventricle above the hypothalamic suprachiasmatic nucleus on the hyperglycemia caused by intracranial injection of 2-deoxy-D-glucose in rats [2].
• Altered endogenous activation of CREB in the suprachiasmatic nucleus of mice with retinal degeneration [3].
• Reduced dopaminergic neurotransmission in the suprachiasmatic nucleus of seasonally obese animals appears to drive noradrenalin and NPY mediated transmissions in other nuclei to induce the obesity syndrome at the appropriate time of year [4].
• The effects of lesions (x) of the suprachiasmatic nucleus (SCN) or paraventricular nucleus (PVN), or pinealectomy (PINX) on gonadal recrudescence, body and fat pad weights, and food intake were examined in photoregressed male Siberian hamsters (Phodopus sungorus sungorus) [5].

Psychiatry related information on Suprachiasmatic Nucleus

• Although the suprachiasmatic nucleus (SCN), site of the circadian clock, contains no intrinsic cholinergic somata, it receives choline acetyltransferase-immunopositive projections from basal forebrain and mesopontine tegmental nuclei that contribute to sleep and wakefulness [6].
• Indeed, systemic as well as local administrations of the serotonin agonist quipazine in the region of the suprachiasmatic nucleus mimic the effects of light on the circadian system of rats, i.e. they induce phase-advances of the locomotor activity rhythm as well as c-FOS expression in the suprachiasmatic nucleus during late subjective night [7].
• Sleep deprivation stimulates serotonin release in the suprachiasmatic nucleus [8].
• Vasopressin mRNA in parvocellular neurons of the rat suprachiasmatic nucleus exhibits increased poly (A) tail length following water deprivation [9].
• The daily timing of rapid eye movement (REM) sleep reflects an interaction between the circadian pacemaker located in the suprachiasmatic nucleus of the hypothalamus (SCN) and a homeostatic process that induces compensatory REM sleep in response to REM sleep loss [10].

High impact information on Suprachiasmatic Nucleus

• CRY1 is highly expressed with circadian periodicity in the mammalian circadian pacemaker, the suprachiasmatic nucleus (SCN) [11].
• The effects of Clock are cell intrinsic and can be observed at the level of single neurons in the suprachiasmatic nucleus [12].
• The highly conserved mouse homolog (m-rigui) is expressed in a circadian pattern in the suprachiasmatic nucleus (SCN), the master regulator of circadian clocks in mammals [13].
• ICER levels are regulated by light by means of the suprachiasmatic nucleus (SCN); transcription is induced during darkness by adrenergic input to the pineal gland from the SCN, which activates the ICER promoter using cyclic AMP and the transcriptional activator CREB [14].
• In mammals, the nighttime production of melatonin is mainly driven by the circadian clock, situated in the suprachiasmatic nucleus of the hypothalamus, which controls the release of norepinephrine from the dense pineal sympathetic afferents [15].

Chemical compound and disease context of Suprachiasmatic Nucleus

• Haloperidol, a non-selective dopamine receptor antagonist, was injected intraperitoneally in to suprachiasmatic nucleus (SCN)-lesioned rats at various phases of the locomotor activity rhythm induced by methamphetamine (MAP) treatment [16].
• The effects of chronic administration of methamphetamine (MAP) on rat locomotor activity rhythm under light-dark (LD) housing and on neuronal activity rhythms from the suprachiasmatic nucleus (SCN) in vitro were investigated [17].
• The role of the suprachiasmatic nucleus (SCN) in photoperiod-dependent hyperglycemia due to D-mannitol (MA) and D-glucose (GL) was investigated using SCN-lesioned rats [18].
• African trypanosomiasis in the rat alters melatonin secretion and melatonin receptor binding in the suprachiasmatic nucleus [19].
• To clarify the effect of a cholinergic agent on free-running period of circadian rhythm, locomotor activities were continuously recorded in the rat implanted with a paraffin pellet mixed with or without carbachol near the suprachiasmatic nucleus [20].

Biological context of Suprachiasmatic Nucleus

• NPAS2 is highly related in primary amino acid sequence to Clock, a transcription factor expressed in the suprachiasmatic nucleus that heterodimerizes with BMAL1 and regulates circadian rhythm [21].
• Overexpression of the human VPAC2 receptor in the suprachiasmatic nucleus alters the circadian phenotype of mice [22].
• Prenatal treatment with the D1-dopamine receptor agonist SKF 38393 or cocaine induces expression of the immediate-early gene c-fos in the fetal rat suprachiasmatic nucleus (SCN) (Weaver et al., 1992) [23].
• Pituitary adenylate cyclase-activating polypeptide and melatonin in the suprachiasmatic nucleus: effects on the calcium signal transduction cascade [24].
• The suprachiasmatic nucleus (SCN), the biological clock, is responsible for a 24-h rhythm in plasma glucose concentrations, with the highest concentrations toward the beginning of the activity period [25].

Anatomical context of Suprachiasmatic Nucleus

• We now report that the suprachiasmatic nucleus of the hypothalamus, which contains the principal circadian clock, and the reuniens and paraventricular nuclei of the thalamus, each independently becomes refractory to melatonin [26].
• Exogenous growth hormone-releasing factor (GRF) has been shown to activate feeding by central mechanisms involving the suprachiasmatic nucleus/medial preoptic area (SCN/MPOA) [27].
• Nocturnal pineal expression of PINA is under the control of a suprachiasmatic nucleus clock mediated by superior cervical ganglion innervation of the pineal [28].
• In all of the animals (n = 3 animals/group), intense hybridization of a monkey GnRH-II riboprobe was evident in the paraventricular nucleus and supraoptic nucleus and to a lesser extent in the suprachiasmatic nucleus, but no age- or sex-related differences were apparent [29].
• Insulin infusion elevated IGF-II concentrations in the dorsomedial hypothalamus (DMH) and suprachiasmatic nucleus, but decreased IGF-II in the paraventricular nucleus, lateral hypothalamus (LtH), and supraoptic nucleus compared to values in control animals [30].

Associations of Suprachiasmatic Nucleus with chemical compounds

• Suprachiasmatic nucleus: use of 14C-labeled deoxyglucose uptake as a functional marker [31].
• Alterations in arginine vasopressin neurons in the suprachiasmatic nucleus in depression [32].
• Substance P-containing neurons of the avian suprachiasmatic nucleus project directly to the nucleus of Edinger-Westphal [33].
• At the molecular level, the light induction of c-fos transcription in the suprachiasmatic nucleus was markedly reduced in the triple mutant mouse compared with either rd/rd or cryptochrome mutant mice [34].
• Preservation of light signaling to the suprachiasmatic nucleus in vitamin A-deficient mice [35].

Gene context of Suprachiasmatic Nucleus

• Clock gene RNA rhythms were blunted in the suprachiasmatic nucleus of mPer2 mutant mice, but not of mPER1-deficient mice [36].
• The three Per genes are rhythmically expressed in the suprachiasmatic nucleus (SCN), the central circadian pacemaker in mammals [37].
• A previous study showed that mice lacking the Cry2 gene had reduced sensitivity to acute light induction of the circadian gene mPer1 in the suprachiasmatic nucleus (SCN) and had an intrinsic period 1 hr longer than normal [38].
• Whereas mPer1 and mPer2 are light-inducible in clock neurons of the hypothalamic suprachiasmatic nucleus, mPer3 is not [39].
• Ca2+/cAMP response element-binding protein (CREB)-dependent activation of Per1 is required for light-induced signaling in the suprachiasmatic nucleus circadian clock [40].

Analytical, diagnostic and therapeutic context of Suprachiasmatic Nucleus

• In situ hybridization studies of melatonin receptor mRNA in several mammals reveal hybridization signals in the hypophyseal pars tuberalis and hypothalamic suprachiasmatic nucleus [41].
• Microinjection of VIP or PACAP into the rodent suprachiasmatic nucleus (SCN) phase shifts the circadian pacemaker and VIP antagonists, and antisense oligodeoxynucleotides have been shown to disrupt circadian function [22].
• Synaptogenesis was studied in the rat suprachiasmatic nucleus (SCN) using quantitative ultrastructural analysis and synapsin I immunohistochemistry [42].
• Synaptogenesis in the rat suprachiasmatic nucleus demonstrated by electron microscopy and synapsin I immunoreactivity [42].
• We investigated photic response of the concentration of vasoactive intestinal polypeptide (VIP) and neuropeptide Y in the rat suprachiasmatic nucleus (SCN) by enzyme immunoassay (EIA) [43].

References