title: Cardiac sympathetic innervation, from a different point of (re)view.
abstract: The audience of basic and clinical scientists is familiar with the notion that the sympathetic nervous system controls heart function during stresses. However, evidence indicates that the neurogenic control of the heart spans from the maintenance of housekeeping functions in resting conditions to the recruitment of maximal performance, in the fight-or-flight responses, across a whole range of intermediate states. To perform such sophisticated functions, sympathetic ganglia integrate both peripheral and central inputs, and transmit information to the heart via 'motor' neurons, directly interacting with target cardiomyocytes. To date, the dynamics and mode of communication between these two cell types, which determine how neuronal information is adequately translated into the wide spectrum of cardiac responses, are still blurry. By combining the anatomical and structural information brought to light by recent imaging technologies and the functional evidence in cellular systems, we focus on the interface between neurons and cardiomyocytes, and advocate the existence of a specific 'neuro-cardiac junction', where sympathetic neurotransmission occurs in a 'quasi-synaptic' way. The properties of such junctional-type communication fit well with those of the physiological responses elicited by the cardiac sympathetic nervous system, and explain its ability to tune heart function with precision, specificity and elevated temporal resolution.
authors.affiliation: Department of Cardiac, Thoracic and Vascular Sciences, via Giustiniani 2, 35128, University of Padova, Padova, Italy.|Department of Biomedical Sciences, via Ugo Bassi 58/B, 35131, University of Padova, Padova, Italy.|Venetian Institute of Molecular Medicine, via G.Orus, 2, 35129, Padova, Italy.
authors.forename: Tania
authors.initials: T
authors.lastname: Zaglia
authors.affiliation: Department of Biomedical Sciences, via Ugo Bassi 58/B, 35131, University of Padova, Padova, Italy.|Venetian Institute of Molecular Medicine, via G.Orus, 2, 35129, Padova, Italy.|CNR institute of Neurosciences, viale Colombo 3, 35133, Padova, Italy.
authors.forename: Marco
authors.identifier: 0000-0002-1102-8709
authors.initials: M
authors.lastname: Mongillo
mesh_terms: D000818:Animals; D006321:Heart / Q000502:physiology*; D006801:Humans; D032383:Myocytes, Cardiac / Q000502:physiology; D009474:Neurons / Q000502:physiology; D013564:Sympathetic Nervous System / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology
keywords: Fight-or-flight response; cardiac synapse; heart; heart rate variability; neuro-cardiac junction; sympathetic neurons; β-adrenoceptors