title: Immunohistochemical analysis of intracardiac ganglia of the rat heart.
abstract: The neurochemistry of intracardiac neurons in whole-mount preparations of the intrinsic ganglia was investigated. This technique allowed the study of the morphology of the ganglionated nerve plexus found within the atria as well as of individual neurons. Intracardiac ganglia formed a ring-like plexus around the entry of the pulmonary veins and were interconnected by a series of fine nerve fibres. All intracardiac neurons contained immunoreactivity to PGP-9.5, choline acetyl transferase (ChAT) and neuropeptide Y (NPY). Two smaller subpopulations were immunoreactive to calbindin or nitric oxide synthase. Furthermore, a subpopulation (approximately 6%) of PGP-9.5/ChAT/NPY-immunoreactive cells lacking both calbindin and nitric oxide synthase (NOS) was surrounded by pericellular baskets immunoreactive to ChAT and calbindin. Vasoactive intestinal peptide (VIP), calcitonin gene-related peptide (CGRP), pituitary adenylate cyclase-activated peptide (PACAP), substance P and tyrosine hydroxylase (TH) immunoreactivity was observed in nerve fibres within the ganglion, but never in neuronal somata. Furthermore, immunoreactivity for NPY was not observed in pericellular baskets surrounding intracardiac neurons, despite being present in all intrinsic neuronal cell bodies. Taken together, the results of this study indicate a moderate level of chemical diversity within the intracardiac neurons of the rat. Such chemical diversity may reflect functional specialisation of neurons in the intracardiac ganglia.
authors.affiliation: Department of Anatomy and Cell Biology, University of Melbourne, 3010 Parkville, Victoria, Australia. r.richardson@pgrad.unimelb.edu.au
authors.forename: R J
authors.initials: RJ
authors.lastname: Richardson
authors.forename: I
authors.initials: I
authors.lastname: Grkovic
authors.forename: C R
authors.initials: CR
authors.lastname: Anderson
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism / Q000648:ultrastructure; D015415:Biomarkers; D001933:Brain Stem / Q000166:cytology / Q000378:metabolism; D064026:Calbindins; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D005260:Female; D005725:Ganglia, Autonomic / Q000166:cytology* / Q000378:metabolism; D005727:Ganglia, Spinal / Q000166:cytology / Q000378:metabolism; D006321:Heart / Q000294:innervation*; D007150:Immunohistochemistry; D008297:Male; D009474:Neurons / Q000145:classification / Q000166:cytology* / Q000378:metabolism; D009478:Neuropeptide Y / Q000378:metabolism; D009479:Neuropeptides / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism; D009620:Nodose Ganglion / Q000166:cytology / Q000378:metabolism; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D051381:Rats; D017207:Rats, Sprague-Dawley; D064030:S100 Calcium Binding Protein G / Q000378:metabolism; D013373:Substance P / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism; D043222:Ubiquitin Thiolesterase / Q000378:metabolism; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism
chemical_list: C495403:Adcyap1 protein, rat; D015415:Biomarkers; D064026:Calbindins; D009478:Neuropeptide Y; D009479:Neuropeptides; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D064030:S100 Calcium Binding Protein G; C482860:UCHL1 protein, human; D013373:Substance P; D014660:Vasoactive Intestinal Peptide; D019001:Nitric Oxide Synthase; D014446:Tyrosine 3-Monooxygenase; D002795:Choline O-Acetyltransferase; D043222:Ubiquitin Thiolesterase; D015740:Calcitonin Gene-Related Peptide