ISSN:
1432-0878
Keywords:
Purkinje Fibres
;
Avian heart
;
Innervation
;
Light and electron microscopy
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary The innervation of the Purkinje fibres in the atrium of the heart of the adult fowl was investigated by light microscopy, using the Champy-Maillet OsO4-ZnI2 technique and the cholinesterase reaction and by electron microscopy. After impregnation of the tissue with OsO4-ZnI2, the dark-stained nerve fibres were clearly visible on the unstained Purkinje fibres. In the upper part of the posterior wall of the right atrium, the diffuse portion of the conducting system is especially richly innervated by varicose and smooth nerve fibres. Some of these fibres are cholinesterase-positive. The terminal axons run in the space between the Purkinje fibres and the fibrocytic envelope. They are either naked or accompanied by Schwann cell processes. In addition to varicosities containing granular vesicles, there are varicosities containing agranular vesicles with oval profiles. In the “en passant” synapses, the width of the synaptic cleft between a varicosity and the Purkinje cell is about 600 Å. The innervation of the Purkinje fibres appears more like the innervation of smooth muscle than that of striated skeletal muscle. The possible role of Purkinje fibres as mechanical receptors is discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00220380
