Cardiac parasympathetic activity was assessed using 24 hour electrocardiographic recordings by measuring the incidence of larger changes in successive RR intervals, which in normal subjects occur frequently but irregularly. In 25 normal subjects the mean number of times per hour in which the change in successive RR interval was greater than 50 ms was 150-250 during waking and 350-450 during sle...

In a series of studies to understand interactions between taste sensation and salivary gland function, we are pursuing experiments to determine the autonomic nervous system control of von Ebner's lingual salivary glands. Electrical stimulation of the glossopharyngeal nerve, which contains the parasympathetic nerve supply to von Ebner's glands, caused a reduction in secretory granules of the gla...

BACKGROUND/AIMS Angiotensin II receptor blockers (ARBs) have been proved to be effective in preventing atrial structural and electrical remodelinq in atrial fibrillation (AF). Previous studies have shown that parasympathetic remodeling plays an important role in AF. However, the effects of ARBs on atrial parasympathetic remodeling in AF and the underlying mechanisms are still unknown. METHODS...

Rationale: Parasympathetic regulation of heart rate is mediated by acetylcholine binding to G protein–coupled muscarinic M2 receptors, which activate heterotrimeric Gi/o proteins to promote G protein–coupled inwardly rectifying K (GIRK) channel activation. Regulator of G protein signaling (RGS) proteins, which function to inactivate G proteins, are indispensable for normal parasympathetic contr...

We have compared the effects of isoflurane, propofol, ketamine and pentobarbital on parasympathetic reflex vasodilatation to investigate their involvement in GABA-mediated synaptic inhibition, enhancement of which is thought to underlie the action of many anaesthetic agents. In cats anaesthetized with urethane-alpha-chloralose, parasympathetic reflex vasodilation in the ipsilateral lower lip wa...

Autonomic nervous system plays an important role in the regulation of mammalian heart, and it is divided into the sympathetic and parasympathetic (vagal) subsystems. The parasympathetic (vagal) control of the atria involves modulation of chronotropic, dromotropic and inotropic activities, but the role of the parasympathetic innervation of the ventricles is still unclear. There is a common misco...

The parasympathetic nervous system plays an important role in the pathophysiology of atrial fibrillation. Catheter ablation, a minimally invasive procedure deactivating abnormal firing cardiac tissue, is increasingly becoming the therapy of choice for atrial fibrillation. This is inevitably associated with the obliteration of cardiac cholinergic neurons. However, the impact on ventricular elect...

The few studies on the psychophysiology of embarrassment have suggested involvement of parasympathetic activation. However, blushing, the hallmark of embarrassment and a prominent symptom in social phobia, is more likely to be produced by cervical sympathetic outflow. Hitherto, there has been no evidence of parasympathetic innervation of the facial blood vessels. In this study, a group of socia...

Pupil size is collectively controlled by the sympathetic dilator and parasympathetic sphincter muscles. Locus coeruleus (LC) activation has been shown to evoke pupil dilation, but how the sympathetic and parasympathetic pathways contribute to this dilation remains unknown. We examined pupil dilation elicited by LC activation in lightly anesthetized rats. Unilateral LC activation evoked bilatera...

Zhong, Yuru, Kung-Ming Jan, Ki Hwan Ju, and Ki H. Chon. Quantifying cardiac sympathetic and parasympathetic nervous activities using principal dynamic modes analysis of heart rate variability. Am J Physiol Heart Circ Physiol 291: H1475–H1483, 2006. First published April 7, 2006; doi:10.1152/ajpheart.00005.2006.—The ratio between low-frequency (LF) and high-frequency (HF) spectral power of heart...