title: [Anatomical relationships of the ionocytes (chloride cells) with the branchial venous compartment: definition of two types of epithelium in fish gills].
abstract: The fish gill, a gas exchanger and osmoregulatory structure, is separated from the external milieu by two well defined types of epithelium. One, the primary lamellar epithelium, faces the venous compartment of the primary lamellae. It contains chloride cells whose extracellular spaces drain into the venous system. The other, the secondary lamellar epithelium, faces the arterio-arterial capillaries of the secondary lamellae and is made-up of an other cell type. This arrangement is seen in all classes of fishes, except Dipnoans, its functional significance is that the activity of the chloride cells directly affects the venous compartment.
mesh_terms: D000818:Animals; D001693:Biological Transport, Active; D002712:Chlorides / Q000378:metabolism; D004847:Epithelial Cells; D005399:Fishes / Q000033:anatomy & histology*; D005880:Gills / Q000098:blood supply / Q000166:cytology* / Q000378:metabolism; D008833:Microcirculation; D014680:Veins
chemical_list: D002712:Chlorides
vernacular_title: Relations anatomiques des ionocytes (cellules à chlorure) avec le compartiment veineux branchial: définition de deux types d'épithélium de la branchie des Poissons.