ISSN:
1432-0878
Keywords:
Pulmonary artery
;
Bufo marinus (toad)
;
Paraneurons
;
Primary monoamines
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary The pulmonary artery of Bufo marinus contains large numbers of bipolar cells situated in the tunica adventitia and in the outer layers of the media. These cells show a bright green-yellow fluorescence (emission spectra 485 nm) after formaldehyde pre-treatment suggesting that they contain a primary monoamine. The most characteristic fine-structural feature of these cells is the presence of numerous dense-cored vesicles (80—300 nm diameter) in their cytoplasm. The cells are in close contact (20 nm gap) with both agranular and granular nerve fibres. Both EM-cytochemical and formaldehyde-induced fluorescence tests indicate that the granule-containing nerve fibres are adrenergic. The agranular nerve fibres form discrete synaptic contacts with pre-and post-synaptic membrane thickenings on the cells. This was never observed with respect to the adrenergic fibres. Each process of the cells is about 45 μm long. The processes do not bear any special relationship to either vessels of the arterial vasa vasorum or medial smooth muscle cells. Their location in the wall of the artery suggests that they are functionally significant with respect to activity of the arterial media.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00233886
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