Differential Control of Cardiac Functions by the Brain

Abstract

1. The idea is introduced that cardiac rate, contractility or atrioventricular (A-V) conduction spread may be controlled independently by the brain. Limited data from reflex studies are cited to support this view. 2. Evidence is presented that individual autonomic post- and preganglionic neurons have quite specific actions on the heart. Premotor and other central neurons can have preferential actions on heart rate, contractility or A-V conduction. 3. The functional implications of selective cardiac control are discussed.

Effects of placebo interventions on gastric motility and general autonomic activity

“…Similar to placebo effects on pain, placebo effects on gastric motility in the present experiment may not be mediated by a global mechanism, such as changes in stress and arousal levels, but may be conveyed quite selectively from the brain to the gut via autonomic fibers supplying specifically the stomach [24]. This notion receives support by an increasing number of neurophysiological and neuroanatomical studies indicating that autonomic outflow to peripheral organs and tissues is organized in a targetspecific manner [25][26][27][28][29]. To examine the autonomic mechanisms of gastric placebo effects in the present study, cardiovascular and electrodermal activities were recorded in parallel with the EGG.…”

The chemical neuroanatomy of vagus nerve stimulation

“…Axons from the parasympathetic portion of the NA terminate in small ganglia associated with the cardiac muscle, with cardio-inhibitory effect (Massari et al, 1995;Gatti et al, 1996Gatti et al, , 1997. In particular, the sinoatrial ganglion, the atrioventricular (AV) ganglion, and the cranioventricular ganglion are the major intracardiac ganglia having a selective influence on heart rate, AV conduction, or left ventricular contractility, respectively (Massari et al, 1995;Gatti et al, 1996Gatti et al, , 1997; for a review, Salo et al, 2006). Functional experiments documented the corresponding cardiac effects obtained after microinjections of sodium glutamate (GLU) in different sites of NA ( Fig.…”

Control of cardiac rate, contractility, and atrioventricular conduction by medullary raphé neurons in anesthetized rats

“…The vagal and sympathetic nerves innervating the pacemaker region, atrioventricular node, and ventricles are distinct, and there is evidence that their functions may be regulated independently, or at least differentially, by basal tone (42) and by the activity of particular brain cell groups (40). Rostrocaudal differences in the nucleus ambiguus have been documented for the vagal control of cardiac functions (11,16,26,27), for example, and the left-right differences in the RVLM for the sympathetic control of the heart (4).…”

“…Several lines of evidence indicate that the central pathways controlling these regional sympathetic supplies are not identical and may be differentially regulated by central commands and reflexes (40).…”