Cell Volume Regulation in the Proximal Tubule of Rat Kidney : Proximal Tubule Cell Volume Regulation.

Published

Journal Article

We developed a dynamic model of a rat proximal convoluted tubule cell in order to investigate cell volume regulation mechanisms in this nephron segment. We examined whether regulatory volume decrease (RVD), which follows exposure to a hyposmotic peritubular solution, can be achieved solely via stimulation of basolateral K[Formula: see text] and [Formula: see text] channels and [Formula: see text]-[Formula: see text] cotransporters. We also determined whether regulatory volume increase (RVI), which follows exposure to a hyperosmotic peritubular solution under certain conditions, may be accomplished by activating basolateral [Formula: see text]/H[Formula: see text] exchangers. Model predictions were in good agreement with experimental observations in mouse proximal tubule cells assuming that a 10% increase in cell volume induces a fourfold increase in the expression of basolateral K[Formula: see text] and [Formula: see text] channels and [Formula: see text]-[Formula: see text] cotransporters. Our results also suggest that in response to a hyposmotic challenge and subsequent cell swelling, [Formula: see text]-[Formula: see text] cotransporters are more efficient than basolateral K[Formula: see text] and [Formula: see text] channels at lowering intracellular osmolality and reducing cell volume. Moreover, both RVD and RVI are predicted to stabilize net transcellular [Formula: see text] reabsorption, that is, to limit the net [Formula: see text] flux decrease during a hyposmotic challenge or the net [Formula: see text] flux increase during a hyperosmotic challenge.

Full Text

Duke Authors

Cited Authors

  • Edwards, A; Layton, AT

Published Date

  • November 2017

Published In

Volume / Issue

  • 79 / 11

Start / End Page

  • 2512 - 2533

PubMed ID

  • 28900833

Pubmed Central ID

  • 28900833

Electronic International Standard Serial Number (EISSN)

  • 1522-9602

International Standard Serial Number (ISSN)

  • 0092-8240

Digital Object Identifier (DOI)

  • 10.1007/s11538-017-0338-6

Language

  • eng