âBiological rhythmicity is fundamental to various physiological processes and these rhythms are described according to frequency, period length, amplitude and phase. Circadian frequency implies that one repetition occurs every 24 hours. In humans, the following physiological variables attain peak levels during sleep: TSH, prolactin, melatonin, ACTH, FSH, LH, cortisol, and lymphocyte and eosinophil counts.
Catecholamine and blood pressure surges occur during the transition from sleep to wakefulness. Other variables, e.g. blood viscosity, platelet adhesiveness, erythrocyte count, FEV, body temperature, blood levels of insulin and Cholesterol, attain peak activity during wakefulness while gastric acid secretion and white cell count peak during the transition from wakefulness to sleep. Circadian rhythms are generated by the SCN in the hypothalamus and are influenced by a variety of factors. These include sleep, cyclical hormone secretion and daily rhythms of core body temperature. Chronobiological disorders are the result of these rhythms failing to remain synchronized with environmental rhythms.
The topics related to circadian rhythms are published in circadian rhythms related journals. One of the official journals of OMICS Group is Journal of Steroids & Hormonal Science that publishes all the articles related to circadian rhythms. The journal is following strict peer review process and maintaining the quality of the articles.
Last date updated on June, 2014