Atrial natriuretic peptide in the innervation of the bovine heart conduction system: relationship with substance P and autonomic innervation--immunohistochemical studies.
Recently, we observed that atrial natriuretic peptide (ANP) immunoreactivity (IR) was present not only in the Purkinje fibres, but also in nerve fibre varicosities in the conduction system of the bovine heart. These findings and previous observations that ANP is able to influence autonomic neurotransmission in the heart, lead us to elucidate the possible occurrence of ANP in the sympathetic and/or parasympathetic nervous systems and/or in various types of peptidergic innervation in the conduction system. The different parts of the conduction system of bovine hearts were dissected out and processed for immunohistochemistry including double-staining, using antisera against ANP, tyrosine hydroxylase and different neuropeptides. We observed that some of the nerve fibre varicosities exhibiting ANP-IR showed substance P-IR and that ANP was present as scattered immunoreactive granules in intracardial, presumably parasympathetic, ganglionic cells. The study shows that ANP is likely to be present in parasympathetic innervation and in afferent nerve endings in the bovine heart conduction system.
Hansson
M
M
Department of Anatomy, University of Umeå, Sweden.
Forsgren
S
S
D000818:Animals; D009320:Atrial Natriuretic Factor / Q000378:metabolism*; D001283:Atrioventricular Node / Q000201:enzymology / Q000378:metabolism; D001341:Autonomic Nervous System / Q000201:enzymology / Q000378:metabolism*; D002417:Cattle; D005725:Ganglia, Autonomic / Q000166:cytology / Q000201:enzymology; D006329:Heart Conduction System / Q000201:enzymology / Q000378:metabolism*; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D009246:NADH Tetrazolium Reductase / Q000378:metabolism; D009412:Nerve Fibers / Q000201:enzymology; D009475:Neurons, Afferent / Q000201:enzymology / Q000502:physiology; D009479:Neuropeptides / Q000378:metabolism; D012849:Sinoatrial Node / Q000201:enzymology / Q000378:metabolism; D013373:Substance P / Q000378:metabolism*
D009479:Neuropeptides; D013373:Substance P; D009320:Atrial Natriuretic Factor; D009246:NADH Tetrazolium Reductase