|
|
||||||||
INNOVATIVE METHODOLOGY
Departments of 1Pharmacology, 2Cell Biology and Anatomy, and 3Medicine, New York Medical College, Valhalla, New York; and 4Department of Physiology, Pontificia Universidad Catolica de Chile, Santiago, Chile
Submitted 26 October 2006 ; accepted in final form 20 July 2007
A medullary thick ascending limb (mTAL) cell line, termed raTAL, has been established from freshly isolated rat mTAL tubules and cultured continuously for up to 75 passages; it retains characteristics of mTAL cells even after retrieval from storage in liquid nitrogen for several months. The cells express Tamm-Horsfall glycoprotein (THP), a TAL-specific marker, grow to confluence, exhibit a polygonal morphology characteristic of epithelial cells, and form "domes." Detection of THP, Na+-K+-2Cl– cotransporter (NKCC2), Na+-K+-ATPase, and renal outer medullary K+ channel (ROMK) was achieved using indirect immunofluorescence and confocal microscopy. Western blot analysis of NKCC2 expression using two different antibodies revealed a band of
160 kDa, and RT-PCR analysis demonstrated the presence of NKCC2 isoforms A and F, which was confirmed by DNA sequencing; transport of Cl– into raTAL cells was inhibited by furosemide. Ouabain- and bumetanide-sensitive oxygen consumption, an index of ion transport activity in the mTAL, was observed in raTAL cells, and the number of domes present was reduced significantly when cells were incubated in the presence of ouabain or bumetanide. The specific activity of Na+-K+-ATPase activity was determined in raTAL cells (0.67 ± 0.18 nmol Pi·µg protein–1·min–1), primary cultures of mTAL cells (0.39 ± 0.08 nmol Pi·µg protein–1·min–1), and freshly isolated mTAL tubules (1.10 ± 0.29 nmol Pi·µg protein–1·min–1), and
30–50% of total cellular ATPase activity was inhibited by ouabain, in accord with other mTAL preparations. This cell line will be used in studies that address biochemical, molecular, and physiological mechanisms in the mTAL.
medullary thick ascending limb; cell culture; renal epithelial cells; renal cell lines
This article has been cited by other articles:
![]() |
S. Hao, H. Zhao, Z. Darzynkiewicz, S. Battula, and N. R. Ferreri Expression and function of NFAT5 in medullary thick ascending limb (mTAL) cells Am J Physiol Renal Physiol, June 1, 2009; 296(6): F1494 - F1503. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. I. Abdullah, P. L. Pedraza, J. C. McGiff, and N. R. Ferreri Calcium-sensing receptor signaling pathways in medullary thick ascending limb cells mediate COX-2-derived PGE2 production: functional significance Am J Physiol Renal Physiol, October 1, 2008; 295(4): F1082 - F1089. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |