Circadian rhythms and autonomic function

GOLOMBEK, DA

Primer on the Autonomic Nervous System

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Oxford; Año: 2011; p. 157 - 159

Circadian rhythms regulate most, if not all, of our physiological functions, including autonomic activity. Such cycles are generated by a master clock located in the suprachiasmatic nuclei (SCN), which coordinate temporal rhythmicity as well as orchestrate peripheral oscillators throughout the body. The SCN is entrained by environmental signals (zeitgebers), the most important being the light–dark cycle. The output of the SCN includes both humoral and neural mechanisms, which are directly related to the autonomic nervous system and, in turn, to the circadian regulation of body functions. This output pathways control metabolic reactions and hormonal secretion, as well as regulate the pancreas, the liver and the adipose tissue, the heart and the kidney (among others) by sympathetic/parasympathetic pathways. An imbalanced temporal regulation of autonomic activity might lead to profound changes in metabolic physiology. In addition, neurovegetative mechanisms exhibit a double modulation by the circadian system and by arousal/sleep-related mechanisms in a homeostatic-like process. Keywords: circadian; suprachiasmatic; entrainment; peripheral oscillators; temporal regulation.