title: Direct synaptic contacts of nitric oxide synthase-immunoreactive nerve terminals on the neurons of the intracardiac ganglia of the guinea pig.
abstract: Immunoelectron microscopy was performed to localize immunoreactivity for nitric oxide synthase (NOS) in guinea pig atria. Many round intracardiac ganglia, close to the openings of the pulmonary veins, contained NOS-immunoreactive neurons. A small number of neurons were immunoreactive, but most of the non-immunoreactive neurons were surrounded by immunoreactive axons. Direct axo-somatic or -spinic synapses from NOS-immunoreactive axon varicosities to intracardiac ganglionic neurons were observed. The present results raise the possibility that nitric oxide plays a role in the neural control of the heart through synapses in the cardiac ganglia.
authors.affiliation: Department of Anatomy, Chiba University School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tanaka
authors.forename: H
authors.initials: H
authors.lastname: Ohshima
authors.forename: H
authors.initials: H
authors.lastname: Esumi
authors.forename: T
authors.initials: T
authors.lastname: Chiba
mesh_terms: D000594:Amino Acid Oxidoreductases / Q000276:immunology / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D005260:Female; D005724:Ganglia / Q000201:enzymology*; D006168:Guinea Pigs; D006321:Heart / Q000294:innervation*; D008297:Male; D016253:Microscopy, Immunoelectron; D009474:Neurons / Q000201:enzymology* / Q000648:ultrastructure; D019001:Nitric Oxide Synthase; D017729:Presynaptic Terminals / Q000201:enzymology* / Q000648:ultrastructure
chemical_list: D019001:Nitric Oxide Synthase; D000594:Amino Acid Oxidoreductases