Volume changes induced by osmotic stress in freshly isolated rat hippocampal neurons.

Journal Article

The degree to which osmotic stress changes the volume of mammalian central neurons has not previously been determined. We isolated CA1 pyramidal cells and measured cell volume in four different ways. Extracellular osmolarity (pio) was lowered by omitting varying amounts of NaCl and raised by adding mannitol; the extremes of pio tested ranged from 134 to 396 mosm/kg. When pio was reduced, cell swelling varied widely. We distinguished three types of cells according to their response: "yielding cells" whose volume began to increase immediately; "delayed response cells" which swelled after a latent period of 2 min or more; and "resistant cells" whose volume did not change during exposure to hypo-osmotic solution. When pio was raised, most cells shrank slowly, reaching minimal volume in 15-20 min. We observed neither a regulatory volume decrease nor an increase. We conclude that the water permeability of the membrane of hippocampal CA1 pyramidal neurons is low compared to that of other cell types. The mechanical support of the plasma membrane given by the cytoskeleton may contribute to the resistance to swelling and protect neurons against swelling-induced damage.

Full Text

Duke Authors

Cited Authors

  • Aitken, PG; Borgdorff, AJ; Juta, AJ; Kiehart, DP; Somjen, GG; Wadman, WJ

Published Date

  • November 1998

Published In

Volume / Issue

  • 436 / 6

Start / End Page

  • 991 - 998

PubMed ID

  • 9799418

International Standard Serial Number (ISSN)

  • 0031-6768

Digital Object Identifier (DOI)

  • 10.1007/s004240050734

Language

  • eng

Conference Location

  • Germany