The mechanism of maitotoxin-induced elevation of the cytosolic free calcium level in rat cerebrocortical synaptosomes.

@article{Satoh2001TheMO,
  title={The mechanism of maitotoxin-induced elevation of the cytosolic free calcium level in rat cerebrocortical synaptosomes.},
  author={E. Satoh and T. Ishii and M. Nishimura},
  journal={Japanese journal of pharmacology},
  year={2001},
  volume={85 1},
  pages={
          98-100
        }
}
The present study was conducted to elucidate the mechanism of the maitotoxin (MTX)-induced increase in intrasynaptosomal free calcium level ([Ca2+]i). The MTX (1 ng/ml)-induced increase in [Ca2+]i was partially inhibited by the omission of extracellular Ca2+ (Ca2+e) or the addition of verapamil, but not by adding nifedipine, omega-agatoxin IVA, omega-conotoxin GVIA and omega-conotoxin MVIIC. An increase in [Ca2+]i in the absence of Ca2+e was sensitive to procaine, TMB-8, genistein and verapamil… Expand
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Results appear to suggest that, in presence of 1 mM extracellular Ca2+ ions, maitotoxin depolarizes synaptosomal plasmamembrane by promoting the influx of extracllular Ca 2+ ions. Expand
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