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

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Influence of inhibitors on increase in intracellular free calcium and proliferation induced by platelet-activating factor in bovine oviductal cells.
    Author: Tiemann U, Neels P, Pöhland R, Walzel H, Löhrke B.
    Journal: J Reprod Fertil; 1999 May; 116(1):63-72. PubMed ID: 10505057.
    Abstract:
    Oviductal endosalpingeal cells were isolated mechanically from heifers and cultured until there was 100% confluency. The cells were loaded with the Ca(2+)-sensitive fluorochrome, fura-2/acetoxymethylester, and cytosolic free calcium ([Ca2+]i) was monitored by spectrofluorimetry. Platelet-activating factor, at a concentration of 30 nmol l-1, induced an intracellular Ca2+ increase in cultured bovine oviductal cells, mainly via influx from the extracellular space. In fura-2-loaded oviductal cells, different Ca2+ channel blockers were investigated to characterize the pathways responsible for the Ca2+ influx. The negative effects of Ni(2+)-, La(3+)-activated K+ channel blockers, such as apamin and charybdotoxin, and Ca2+ channel blockers, such as dotarizine, on the platelet-activating factor-induced [Ca2+]i increase indicate the minor participation of the voltage-gated Ca2+ channels. TMB-8 and flufenamic acid blocked the platelet-activating factor-induced Ca2+ increase directly on non-selective cationic channels or acted via a Ca2+ release-triggered Ca2+ influx. Platelet-activating factor, at concentrations of 1.25 mumol l-1 and 2.5 mumol l-1, significantly stimulated the proliferation and depolarization of oviductal cells, but 10 mumol l-1 significantly decreased both parameters and exerted a cytotoxic effect on cells. After incubation with TMB-8 or flufenamic acid, the cell proliferation was inhibited in a concentration-dependent manner, with IC50 values of 26.57 mumol l-1 and 95.29 mumol l-1, respectively. The depolarization was significantly inhibited at 50 mumol l-1 for both TMB-8 and flufenamic acid. The results of the present study may contribute to further understanding of the mechanism behind the actions of platelet-activating factor on oviductal cells.
    [Abstract] [Full Text] [Related] [New Search]