BACKGROUND Diurnal variations in the incidence of events such as heart attack and stroke suggest a role for circadian rhythms in the etiology of cardiovascular disease. The aim of this study was to assess the influence of the suprachiasmatic nucleus (SCN) circadian clock on cardiovascular function. METHODOLOGY/PRINCIPAL FINDINGS Heart rate (HR), blood pressure (BP) and locomotor activity (LA)...

BACKGROUND Disruption of the circadian rhythm is a key feature of bipolar disorder. Variation in genes encoding components of the molecular circadian clock has been associated with increased risk of the disorder in clinical populations. Similarly in animal models, disruption of the circadian clock can result in altered mood and anxiety which resemble features of human mania; including hyperacti...

BACKGROUND AND OBJECTIVES Although circadian variation in the onset of acute myocardial infarction (AMI) has been reported in a number of studies, not much is known about the impact of circadian variation on 12-month mortality. The aim of this study was to investigate the impact of circadian variation on 12-month mortality in patients with AMI. SUBJECTS AND METHODS Eight hundred ninety two pa...

Malignant ventricular tachyarrhythmias and sudden cardiac death exhibit a circadian variation with a distinct peak during morning hours. The underlying cause for this observation appears to be complex and multifactorial. For example, in a field study in patients with out-of-hospital cardiac arrest, Arntz and co-workers found a clear diurnal variation in patients with ventricular fibrillation bu...

Nitric Oxide as an Efferent Modulator of Circadian Pacemaker Neurones in the Eye of the Marine Mollusc Bulla gouldiana. Background: Nitric oxide synthase NOS is essential for the synthesis of nitric oxide. The diurnal oscillation of NOS in the hippocampus is.Nitric oxide NO plays an important role in phase-shifting of circadian neuronal activities in the suprachiasmatic nucleus and circadian be...

To test the hypothesis that there is a functional modulation of conventional EEG bands associated with preparatory attention, putative changes in the spontaneous brain rhythms and their associated cerebral sources were addressed. The goals of the present report were, first, to find the brain areas with maximal rhythmic activity before warning and imperative stimuli in a classic contingent negat...