title: Strategy for the development of a matched set of transport-competent, angiotensin receptor-deficient proximal tubule cell lines.
abstract: In the proximal convoluted tubule (PCT) angiotensin II (Ang II) modulates fluid and electrolyte transport through at least two pharmacologically distinct receptor subtypes: AT(1) and AT(2). Development of cell lines that lack these receptors are potentially useful models to probe the complex cellular details of Ang II regulation. To this end, angiotensin receptor- deficient mice were bred with an Immortomouse(R), which harbors a thermolabile SV40 large-T antigen (Tag). S1 PCT segments from kidneys of F(2) mice were microdissected, placed in culture, and maintained under conditions that enhanced cell growth, i.e., promoted Tag expression and thermostability. Three different types of angiotensin receptor-deficient cell lines, (AT(1A) [-/-], Tag [+/-]), (AT(1B) [-/-], Tag [+/-]), and (AT(1A) [-/-], AT(1B) [-/-], Tag [+/+]), as well as wild type cell lines were generated. Screening and characterization, which were conducted under culture conditions that promoted cellular differentiation, included: measurements of transepithelial transport, such as basal monolayer short-circuit current (Isc; -3 to 3 microA/cm2), basal monolayer conductance (G, 2 to 10 mS/cm2), Na3(+)-phosphate cotransport (DeltaIsc of 2 to 3 microA/cm(2) at 1 mM), and Na(3)(+)-succinate cotransport (DeltaIsc of 1 to 9 microA/cm(2) at 2 mM). Morphology of cell monolayers showed an extensive brush border, well-defined tight junctions, and primary cilia. Receptor functionality was assessed by Ang II-stimulated beta-arrestin 2 translocation and showed an Ang II-mediated response in wild type but not (AT(1A) [-/ -], AT(1B) [-/-]) cells. Cell lines were amplified, yielding a virtually unlimited supply of highly differentiated, transport-competent, angiotensin receptor-deficient PCT cell lines.
authors.affiliation: Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106-4970, USA. philip.woost@case.edu
authors.forename: Philip G
authors.initials: PG
authors.lastname: Woost
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Kolb
authors.forename: Margaret
authors.initials: M
authors.lastname: Finesilver
authors.forename: Irene
authors.initials: I
authors.lastname: Mackraj
authors.forename: Hans
authors.initials: H
authors.lastname: Imboden
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Coffman
authors.forename: Ulrich
authors.initials: U
authors.lastname: Hopfer
mesh_terms: D000804:Angiotensin II / Q000235:genetics / Q000378:metabolism; D000818:Animals; D019390:Arrestins / Q000378:metabolism; D001692:Biological Transport / Q000502:physiology; D001947:Breeding; D018929:Cell Culture Techniques; D002454:Cell Differentiation; D002460:Cell Line; D004573:Electrolytes / Q000378:metabolism; D005838:Genotype; D007150:Immunohistochemistry; D007687:Kidney Tubules, Proximal / Q000166:cytology* / Q000378:metabolism; D051379:Mice; D009154:Mutation; D012333:RNA, Messenger / Q000378:metabolism; D011945:Receptors, Angiotensin / Q000235:genetics* / Q000378:metabolism; D000071560:beta-Arrestin 2; D000071557:beta-Arrestins
chemical_list: C000605258:Arrb2 protein, mouse; D019390:Arrestins; D004573:Electrolytes; D012333:RNA, Messenger; D011945:Receptors, Angiotensin; D000071560:beta-Arrestin 2; D000071557:beta-Arrestins; D000804:Angiotensin II