These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Ca2+ changes and 86Rb efflux activated by hyposmolarity in cerebellar granule neurons.
    Author: Morales-Mulia S, Ordaz B, Quesada O, Pasantes-Morales H.
    Journal: J Neurosci Res; 1998 Sep 01; 53(5):626-35. PubMed ID: 9726433.
    Abstract:
    Hyposmotic swelling increased 86Rb release in cultured cerebellar granule neurons (1 day in vitro [DIV]) with a magnitude related to the change in osmolarity. 86Rb release was partially blocked by quinidine, Ba2+, and Cs+ but not by TEA, 4-AP, or Gd3+. 86Rb efflux decreased in Cl(-)-depleted cells or cells treated with DDF or DIDS, suggesting an interconnection between Cl- and K+ fluxes. Swelling induced a substantial increase in [Ca2+]i to which both external and internal sources contribute. However, 86Rb efflux was independent of [Ca2+]0, unaffected by depleting the endoplasmic reticulum (ER) by ionomycin or thapsigargin and insensitive to charybdotoxin, iberiotoxin, and apamin. Swelling-activated 86Rb efflux in differentiated granule neurons after 8 DIV, which express Ca2+-sensitive K+ channels, was not different from that in 1 DIV neurons, nor in time course, net release, Ca2+-dependence, or pharmacological sensitivity. We conclude that the swelling-activated K+ efflux in cerebellar granule neurons is not mediated by Ca2+-sensitive large conductance K+ channels (BK) as in many cell types but resembles that in lymphocytes where it is possibly carried by voltage-gated K+ channels.
    [Abstract] [Full Text] [Related] [New Search]