The circadian variation in neuronal discharge activity recorded in vitro from the Syrian hamster suprachiasmatic nucleus (SCN), identified as a circadian clock, was used as an index of SCN circadian function. SCN neurones (n = 89) following in vitro commissural section of the paired SCN showed a similar peak in spontaneous discharge activity during the projected light phase (between CT 06.00 an...

The suprachiasmatic nuclei (SCN) coordinate the daily sleep-wake cycle by generating a circadian rhythm in electrical impulse frequency. While period and phase of the SCN rhythm have been considered as major output parameters, we propose that the waveform of the rhythm of the SCN also has significance. Using implanted micro-electrodes, we recorded SCN impulse frequency in freely moving mice and...

The coordinated activity of thousands of cellular oscillators in the suprachiasmatic nuclei (SCN) temporally regulates mammalian physiology to anticipate daily environmental changes across the seasons. The phasing of clock gene expression varies according to anatomical location in the SCN and is thought to encode photoperiodic information. However, it is unclear whether similar variations in ph...

The suprachiasmatic nucleus (SCN) of the hypothalamus is the master mammalian circadian clock. The SCN is highly specialized because it is responsible for generating a near 24 h rhythm, integrating external cues, and translating the rhythm throughout the body. Currently, our understanding of the developmental origin and genetic program involved in the proper specification and maturation of the ...

Oratile Semong and Bareki Shima Batlokwa The monitoring of thiocyanate (SCN−) in food is consumer health safety relevance. In this work, a colorimetric method for the detection SCN− milk using silver nanoparticles (AgNPs) nanozyme presented.

Gastric peroxidase (GPO) was purified to apparent homogeneity to characterize its major physiological electron donor. The enzyme (RZ = 0.7), with a subunit molecular mass of 50 kDa, is a glycoprotein, with a relative abundance of aspartic and glutamic acid over arginine and lysine. It has a Soret maximum at 412 nm, which is shifted to 426 nm by H2O2 due to formation of compound II. Although the...

Cryptochrome (Cry) 1 and Cry2 are regarded as critical components for circadian rhythm generation in mammals. Nevertheless, cultured suprachiasmatic nucleus (SCN) of neonatal Cry double deficient (Cry1(-/-)/Cry2(-/-)) mice exhibit circadian rhythms that damp out in several cycles. Here, by combining bioluminescence imaging of Per1-luc and PER2::LUC with multielectrode recording, we show develop...

During late fetal and early neonatal life, the maternal circadian system coordinates the timing of a circadian clock in the hypothalamic suprachiasmatic nuclei (SCN) to the prevailing light-dark cycle. The role of the maternal SCN in the process of maternal coordination was investigated in rats. Complete lesions of the maternal SCN on day 7 of gestation disrupted rhythms of SCN glucose utilizat...

The suprachiasmatic nucleus (SCN), the mammalian circadian pacemaker, receives information about ambient light levels through the retinohypothalamic tract. This information resets the molecular clock of SCN neurons, thereby entraining overt animal behavior and physiology to the solar cycle. Progress toward functional characterization of retinal influences on the SCN has been hampered by limitat...

Circadian rhythm disturbances are a common symptom among individuals with mood disorders. The suprachiasmatic nucleus (SCN), in the ventral part of the anterior hypothalamus, orchestrates physiological and behavioral circadian rhythms. The SCN consists of self-sustaining oscillators and receives photic and nonphotic cues, which entrain the SCN to the external environment. In turn, through synap...