View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Kidney International, Vol. 33 (1988), pp. 1—7 EDITORIAL REVIEW A standard nomenclature for structures of the kidney THE RENAL COMMISSION OF THE INTERNATIONAL UNION OF PHYSIOLOGICAL SCIENCES (IUPS) Prepared by WILHELM KRIz, Co-Chair, Heidelberg, Federal Republic of Germany LISE BANKIR, Co-Chair, Paris, France In consultation with RUTH ELLEN BULGER, Houston, USA MAURICE B. BURG, Bethesda, USA OLGA A. GONCHAREVSKAYA, Leningrad, USSR MASASHI IMAI, Osaka, Japan BRIGITTE KAISSLING, Basel, Switzerland ARVID B. MAUNSBACH, Aarhus, Denmark DAVID B. MOFFAT, Cardiff, UK FRANc0IS MOREL, Paris, France TREFOR 0. MORGAN, Melbourne, Australia YuRI V. NATOCHIN, Leningrad, USSR C. Cijo TISI-IER, Gainesville, USA MANJERI A. VENKATACHALAM, San Antonio, USA GUILLERMO WHITTEMBURY, Caracas, Venezuela FRED S. WRIGHT, New Haven, USA Editors Note: This paper, "Standard nomenclature for struc-nephron to three types of nephrons, of four main tubular parts tures of the kidney," was prepared at the request of the Renal (proximal tubule, intermediate tubule, distal tubule, collecting Commission of the International Union of Physiological Sci-duct) to several subdivisions of those parts, and of homogeneity ences (IUPS). The information is being published, by a jointof cells within a given part to identification of several types of editorial decision, simultaneously in the January, 1988 issues ofcells within a part or subdivision. With our heightened ability to THE AMERICAN JOURNAL OF PHYSIOLOGY: RENAL, dissect the many components of the kidney, both anatomically FLUID AND ELECTROLYTE PHYSIOLOGY, KIDNEY IN- and functionally, there is an increasing need to convey to our TERNATIONAL, and PFLUGERS ARCHly. colleagues precisely which structure we were working with. The Editors have chosen, deliberately, to duplicate publica-The following standard nomenclature is disseminated to help tion of this document in the above three journals, to insure themeet that need. widest possible dissemination of this terminology, which has The project was undertaken at the request of the Renal been adopted simultaneously by each of the three journals. Commission of the International Union of Physiological Sci- ences (IUPS). It is the hope of the Commission that the JAMES A. SCHAFER, Ph.D., Editor, American Journal ofnomenclature proposed herein may be widely adopted. We Physiology: Renal, Fluid and Electrolyte Physiology recommend that when disagreement arises—as is bound to THOMAS E. ANDREOLI, M.D., Editor, Kidney Internationalhappen—the author(s) may indicate that the name which he or KLAUS THURAU, M.D., Coordinating Editor, Pflügers Archiv—she applies to a given structure is synonymous with one of the European Journal of Physiology elements designated in Table 1 or Figures 1 and 2 of the present Preamble report. Discoveries which alter the schema should be called to the attention of one of the co-chairs, W. Kriz, or L. Bankir. The kidney is an organ of complex structure and function, a References have been deliberately omitted because it would fact that is increasingly revealed as our investigations proceed.have been cumbersome to include the many sources that served We have witnessed a progression from recognition of a single as a basis for the recommendations. Those needing particulars on the sources should contact one of the co-chairs. Received for publication August 3, 1987 Heinz Valtin, Chair © 1988 by the International Society of Nephrology Renal Commission of LUPS (1980—86) 1 2 Standard nomenclature Kidney structure Explanation Kidney structure Explanation Main Divisions Giant bundles Fusion of several bundles. Cortex (C) Simple type The simple type contains Cortical labyrinth Complex type only descending and ascend- Cortex corticis ing vasa recta; the complex Medullary rays type includes the descending thin limbs of short loops of Medulla Henle. Outer medulla (OM) Interbundle capillary Only for the inner stripe cap- Outer stripe (OS) plexus illary plexus. Inner stripe (IS) Renal lymphatics Vascular bundles Renal nerves Interbundle region Inner medulla (IM) Renal interstitium Lipid laden interstitial Papilla The papilla is that part of the Crest inner medulla which projects cells into the pelvis. In many kid- neys a crest is developed in- Nephrons stead of a papilla. Nephron—Types Renal pelvis Superficial nephrons Those originating from a su- Pelvic cavity Midcortical nephrons Pelvic extension Extensions of the pelvic cavi- perficial, midcortical, or jux- Juxtamedullary nephronstamedullary glomerulus (see ty along the blood vessels. later). A less strict definition Secondary pouches Extensions of the pelvic cavi- for a superficial nephron says ty around the edges of the that it touches the renal sur- pelvic septa. face. Renal sinus Short-looped nephrons Henle's loop turning back in Renal hilum the outer medulla (or cortex). For multilobar, multipapil- Cortical nephrons Henle's loop turning back in laty kidneys the follow- the cortex. ing additional terms are Long-looped nephrons Henle's loop turning back in necessary: the inner medulla. Renal column (Column of Bertin) N.B.: The two divisions in Major calices, minor nephron types do not always calices coincide: for example, juxta- Renal artery, anterior medullary nephron is not and posterior divisions necessarily synonymous with Segmental artery long-looped nephron. Super- ficial as well as juxtamedul- Vessels, nerves, and lary nephrons may have long interstitium or short loops. Renal vasculature Renal artery (vein) Interlobar artery (vein) Nephron—Main divisions Arcuate artery (vein) Renalcorpuscle Cortical radial artery This term is much more ap- Bowman's capsule (vein) propriate in describing the Glomerulus The term "glomerulus" (plu- course of these vessels; it re- Glomerular lobule ral: glomeruli) is widely used places the term interlobular to designate the entire renal artery. corpuscle. In the present sys- Perforating radial artery tem the glomerulus is more Stellate vein precisely termed "glomerular Afferent arteriole tuft." Efferent arteriole Urinary space Often called Bowman's Welling point space. Glomerular capillaries Tubular portions of the Peritubular capillaries nephron Descending vasa recta Proximal tubule Ascending vasa recta Intermediate tubule The term "Intermediate tu- Vascular bundles Distal tubule bule" has formerly been Primary bundles used. It is regarded as a Secondary bundles Fusion of two primary bun- very appropriate term and is dles. therefore reintroduced to designate the entire thin Abbreviations are in parenthesis. limb. Standard nomenclature 3 Kidney structure Explanation Kidney structure Explanation Proximal convolution N.B. This micro-anatomical c. Proximal tubule Loop of Henle subdivision of the nephron • Neck segment Only present in some spe- Long loop, short tubule is independent from cies; it may be considered as loop, cortical loopthe above one. The distal a tubular elongation of Bow- Distal convolution convolution does not com- man's capsule. prise the same segments as • Convoluted part Situated in the cortical laby- the distal tubule (Table 1). (pars convoluta) or rinth. The term "loop of Henle" Proximal convoluted comprises the straight part of tubule (PCT) the proximal tubule (thick de- • Straight part (pars Situated in the medullary ray scending limb), the interme- recta) or Proximal of cortex and in the outer diate tubule (thin descending straight tubule (PST) stripe of the outer medulla. and ascending limbs) and the Note that the straight parts straight part of the distal tu- of the juxtamedullary neph- bule (thick ascending limb). rons are not straight, but de- Nephron—Details scend tortuously through the a. Renal corpuscle outer stripe. They are de- Types fined as "straight parts" by their location in the outer Superficial renal cor- Those giving rise to an effer- stripe. puscles (superficial ent arteriole which touches glomeruli) the renal surface. A less Subdivisions: (de- strict definition comprises all fined ultra- glomeruli establishing the structurally) most superficial layer of gb- Sl (segment) (or P1)Comprises the beginning and meruli. SI cells middle portions of the convo- Midcortical renal cor- The term comprises all gb- luted part. Transition to S2 is puscles (midcortical meruli which are neither su- gradual. glomeruli) perficial nor juxtamedullary. S2 (segment) (or P2)Comprises the end portions Juxtamedullary renal Those giving rise to an effer- S2 cells of the convoluted part and corpuscles (juxtame-ent arteriole which turns to- the beginning portions of the dullary glomeruli) wards the medulla and splits straight part. Transition to S3 into descending vasa recta. is abrupt in some species Components (rat, dog), gradual in others (rabbit). Parietal cells of Bow- S3 (segment) (or P3)Comprises the remaining por- man's capsule S3 cells tions of the straight part. Peripolar cells These cells are modified cells Generally, all proximal tu- of Bowman's capsule which bules lying in the outer stripe contain granules. are S3 segments. Podocytes Synonymous with visceral cells of Bowman's capsule or Instead of Sl, S2, and S3 the gbomerular epithelial cells. abbreviations P1, P2, and P3 Filtration slit are widely used. The "S" re- Slit diaphragm fers to "segment" and "P" Endothelial cells to "proximal." Mesangium Mesangial cells d. Intermediate tubule Mesangial matrix Descending thin limb Glomerular basement of Henle's loop (pars membrane (GBM) descendens)