title: Ultrastructure of the nephron of grey mullets (Mugil cephalus L. and Liza saliens Risso 1810).
abstract: Mugil cephalus and Liza saliens nephrons consist of renal corpuscles, neck segments, first, second and third proximal segments, collecting segments and collecting ducts. The glomerular endothelial cells are fenestrated showing a thin diaphragm. Mesangial cells are located around and between the capillaries, suggesting a role in vessel contraction; they show no phagocytic ultrastructural features. An extensive part of the podocyte surface lies flat on the glomerular basement membrane; this characteristic is probably related to the diminishing of the glomerular filtration rate. Podocytes show large multivesicular bodies, lysosomes and vesicles with a dense bar. Large globules in the podocytes point to their possible secretory activity. The first proximal segment is made up of principal cells with a well developed brush border and tightly packed basal infoldings, and scarce ciliated cells. The second proximal segment consists of principal cells, with loose-packed microvilli and numerous deep basal invaginations, ciliated cells and dark cells. The third proximal segment shows cells with irregularly arranged microvilli and a basal labyrinth, and some ciliated cell. The collecting segment and the collecting duct cells were characterized by apical mucous droplets; the latter also show a well developed basal labyrinth and are surrounded by a layer of smooth muscle cells.
authors.affiliation: Department of Cell Biology, Faculty of Biology, University of Murcia, Spain.
authors.forename: E L
authors.initials: EL
authors.lastname: Morales
authors.forename: J
authors.initials: J
authors.lastname: Meseguer
authors.forename: M T
authors.initials: MT
authors.lastname: Lozano
authors.forename: B
authors.initials: B
authors.lastname: Agulleiro
mesh_terms: D000818:Animals; D004727:Endothelium / Q000648:ultrastructure; D007678:Kidney Glomerulus / Q000648:ultrastructure; D007684:Kidney Tubules / Q000648:ultrastructure; D008854:Microscopy, Electron; D008871:Microvilli / Q000648:ultrastructure; D009399:Nephrons / Q000648:ultrastructure*; D010473:Perciformes / Q000033:anatomy & histology*; D012623:Seawater