circadian pacemaker

circadian pacemaker

A cluster of hypothalamic neurons, the activity of which fluctuates in ± 24-hour cycles, resides in the pineal gland—an aggregate of parenchymal cells surrounded by a neuroglial network with direct retinal innervation (retinohypothalamic tract), which is thought to act by secreting melatonin at night—weighs 100–180 mg, and derives embryologically from the ependyma at the roof of the third ventricle. In rats, the biogenic oscillator/internal clock resides in the ventral hypothalamus; in hamsters, in the suprachiasmatic nucleus. The circadian pacemaker influences the pineal gland.

circadian pacemaker

A cluster of neurons, the activity of which fluctuates in ± 24 hr cycles; the CP resides in the pineal gland, weighs 100-180 mg, and derives embryologically from the ependyma at the roof of the 3rd ventricle; the CP influences the pineal gland, which produces melatonin at night. See Bright light therapy, Chronotherapy, Circadian rhythm, Melatonin, Seasonal affective disorder, Zeitgeber.
References in periodicals archive ?
Timing of human sleep: recovery process gated by a circadian pacemaker. Am J Physiol.
Although the primary circadian pacemaker resides in the hypothalamus, organs throughout the body--including skeletal muscle--have clock and clock-controlled genes that display circadian rhythms.
Circadian pacemaker in the Bursatella eye: properties of the rhythm and its effect on locomotor behavior.
Moran et al., "Mop3 is an essential component of the master circadian pacemaker in mammals," Cell, vol.
The foremost function of the SCN is to act as a cardinal circadian pacemaker so as to control the sleep (i.e., rest) and wake (i.e., activity) cycle.
Two peaks in the activity rhythm of cockroaches controlled by one circadian pacemaker. Journal of Comparative Physiology 137:249-254.
In the circadian pacemaker SCN, the QPCR analysis ( n = 3 for each time point, equals to n = 12 in each group) showed an obvious effect of time on the expression profile of Clock, Bmal1, Per2 in sham group [ P < 0.01, P < 0.01, P < 0.05, ANOVA, [Figure 2]a,[Figure 2]b,[Figure 2]c.
Borbely, "Timing of human sleep: recovery process gated by a circadian pacemaker," American Journal of Physiology-Endocrinology and Metabolism, vol.
The data were aligned with the melatonin rhythm which is a hormonal marker of the human brain circadian pacemaker, i.e.
Circadian modulation of sleep pressure, or circadian variations in susceptibility to sleep, primarily depend on the signal from the circadian pacemaker located in the hypothalamic suprachiasmatic nuclei, which is in the close interaction with various environmental and social markers [20].
Borbely, "Timing of human sleep: recovery process gated by a circadian pacemaker," American Journal of Physiology--Regulatory, Integrative and Comparative Physiology, vol.
As is the case in a mutation of the twenty-four gene, when the Ataxin-2 gene is not present, very little PER protein is found in the circadian pacemaker neurons of the brain, and the fly's sleep-wake rhythm is disturbed.

Full browser ?