title: Mitochondria-rich cells in gills and skin of an African lungfish, Protopterus annectens.
abstract: We used scanning electron microscopy, the vital dye DASPEI and an antibody to the inner mitochondrial membrane to study the presence and localisation of mitochondria-rich cells in the gills and skin (opercular, dorsal and ventral) of the lungfish Protopterus annectens in its free-swimming conditions and at the beginning of aestivation. In the free-swimming period, the gills were short and thick and the pavement cells were extremely large (30-40 microns). The mitochondria-rich cells, which were distributed in the secondary and primary epithelium, occurred as two morphologically different types, i.e. elongated and oval, similar to the alpha and beta chloride cells of fresh water teleosts. In the skin, only one type of mitochondria-rich cells was found, resembling the alpha chloride cells. All the mitochondria-rich cells distributed in the gills and skin were labelled with anti Ca(2+)-ATPase serum indicating the possible uptake of Ca2+ at freshwater chloride cell level. At the start of aestivation, the skin and gills were covered by a thick layer of mucus and the epithelium of the gills was reduced. The mitochondria-rich cells were almost completely covered by the pavement cells.
authors.affiliation: Dipartimento di Biologia Sperimentale, Ambientale ed Applicata (DIBISAA), Sezione di Neuroendocrinologia e Biologia dello Sviluppo, Università di Genova, Viale Benedetto XV 5, 16132 Genoa, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Sturla
authors.forename: M A
authors.initials: MA
authors.lastname: Masini
authors.forename: P
authors.initials: P
authors.lastname: Prato
authors.forename: C
authors.initials: C
authors.lastname: Grattarola
authors.forename: B
authors.initials: B
authors.lastname: Uva
mesh_terms: D000818:Animals; D000252:Calcium-Transporting ATPases / Q000276:immunology / Q000648:ultrastructure; D020405:Dermis / Q000033:anatomy & histology / Q000098:blood supply / Q000648:ultrastructure; D000078404:Epidermal Cells; D004817:Epidermis / Q000033:anatomy & histology* / Q000648:ultrastructure; D004956:Estivation; D005260:Female; D005399:Fishes / Q000033:anatomy & histology*; D005456:Fluorescent Dyes / Q000378:metabolism; D005880:Gills / Q000166:cytology* / Q000648:ultrastructure; D020397:Goblet Cells / Q000378:metabolism / Q000648:ultrastructure; D007150:Immunohistochemistry; D007425:Intracellular Membranes / Q000276:immunology / Q000648:ultrastructure; D008297:Male; D008855:Microscopy, Electron, Scanning; D008856:Microscopy, Fluorescence; D008928:Mitochondria / Q000648:ultrastructure*; D009093:Mucus / Q000378:metabolism; D011726:Pyridinium Compounds / Q000378:metabolism
chemical_list: D005456:Fluorescent Dyes; D011726:Pyridinium Compounds; C025042:2-(dimethylaminostyryl)-1-ethylpyridinium; D000252:Calcium-Transporting ATPases