Morphology of the Intrinsic Cardiac Nervous System in the Dog: A Whole-Mount Study Employing Histochemical Staining with Acetylcholinesterase

Abstract

The intrinsic cardiac nervous system is known to be important both in the prevention and treatment of risky heart diseases. The present study was designed to determine the topography and 3-dimensional architecture of the intrinsic nervous system in the canine heart highlighting the differences of this system in dogs and humans. The morphology of the intrinsic cardiac neural plexus was revealed with a histochemical method using acetylcholinesterase in whole hearts of 18 mongrel dogs and examined with the aid of dissecting stereoscopic and contact microscopes. The present study identified 13 locations between the canine ascending aorta and pulmonary trunk, around the pulmonary veins, and on every side of the superior vena cava, through which mediastinal cardiac nerves accessed the canine heart. Intrinsic nerves from these locations extended within the canine epicardium by seven neuronal subplexuses. Intrinsic nerves and ganglia were found to be widely distributed in topographically consistent atrial and ventricular regions. In general, the canine right atrium, including the sinoatrial node, was innervated by two subplexuses, the wall of the left atrium by three, and the right and left ventricles by two subplexuses. Depending on the age of the animal, the number of intrinsic ganglia per one canine heart might range from 400 up to 1,500. By taking into account the ganglion size and potential approximate number of neurons residing inside a ganglion of a certain size, it was estimated that on average about 80,000 intrinsic neurons are associated with the canine heart. A comparative analysis of the morphological patterns of the canine and human intrinsic cardiac neural plexuses showed that the topographies of these plexuses may be considered as quite similar, but the structural and quantitative differences of the intrinsic cardiac neural subplexuses between dogs and humans are significant.

Role of the Autonomic Nervous System in Modulating Cardiac Arrhythmias

“…6 The intrinsic cardiac ANS thus forms a complex network composed of GP, concentrated within epicardial fat pads, and the interconnecting ganglia and axons. 5,6,18 These GP may function as integration centers that modulate the intricate autonomic interactions between extrinsic cardiac ANS and intrinsic cardiac ANS. 19 Several primary groups of GP in the atria and ventricles have been identified.…”

Valsartan Reduced Atrial Fibrillation Susceptibility by Inhibiting Atrial Parasympathetic Remodeling through MAPKs/Neurturin Pathway

“…Previous findings hint that atrial parasympathetic nerve distribution pattern could alter atrial electrophysiology [26]. The regional differences in the distribution of the parasympathetic innervation could resulting the nonuniformity of acetylcholine concentration and shortening of AERP when parasympathetic nerve was stimulated [33].…”

“…Cardiac ganglia were defined as nerve bundles containing 1 or more neuronal cell bodies [25,26]. Briefly, the deparaffinized and hydrated sections were incubated with primary anti-choline acetyltransferase (ChAT, MILLIPORE, Boston, MA, USA) antibody overnight at 4°C, and then with secondary antibody (IgG-HRP conjugates, Zhongshan, Beijing, China) at 37°C for 20 minutes.…”

Neuro-cardiac interaction in malignant ventricular arrhythmia and sudden cardiac death

“…Dense parasympathetic innervation is demonstrated in all species studied including the mouse (Rysevaite et al 2011), guinea pig (Batulevicius et al. 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 2005), rabbit (Pauziene et al 2016), cat (Johnson et al 2004, dog (Pauza et al 2002), pig (Ulphani et al 2010), sheep (Saburkina et al 2010) and human ventricle (Pauza et al 2000;Kawano et al 2003).…”