title: Intranuclear bundles of microfilaments and microtubules in chromaffin cells of the auricle of the heart of a lungfish, Protopterus aethiopicus.
abstract: Intranuclear microtubular-microfilamentous rod-like inclusions were investigated in chromaffin cells of the auricle of the heart of lungfishes. In conventional electron microscopy, these inclusions reveal a wide variety in appearance, depending on their orientation to the plane of sectioning. Whereas originally they were merely interpreted as a bundle of microfilaments, application of a goniometer stage showed the rod- or spindle-shaped intranuclear inclusions to have a basic substructure of parallel arranged microtubules among microfilaments, which are clearly connected to chromatin granules, occasionally penetrating dense areas of chromatin. The chemical nature and biological significance of these structures, which so far remain enigmatic, are discussed.
authors.affiliation: Institute of Histology and Microscopic Anatomy, University of Antwerp, Belgium.
authors.forename: D W
authors.initials: DW
authors.lastname: Scheuermann
authors.forename: D
authors.initials: D
authors.lastname: Adriaensen
authors.forename: M H
authors.initials: MH
authors.lastname: De Groodt-Lasseel
mesh_terms: D008841:Actin Cytoskeleton / Q000648:ultrastructure*; D000818:Animals; D002467:Cell Nucleus / Q000648:ultrastructure*; D002838:Chromaffin System / Q000648:ultrastructure*; D003599:Cytoskeleton / Q000648:ultrastructure*; D004298:Dopamine / Q000032:analysis; D004759:Enterochromaffin Cells / Q000032:analysis / Q000648:ultrastructure*; D005399:Fishes / Q000033:anatomy & histology*; D006325:Heart Atria / Q000166:cytology*; D008854:Microscopy, Electron; D008870:Microtubules / Q000648:ultrastructure*
chemical_list: D004298:Dopamine