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PubMed · 1706630

[Latrotoxin channels. Permeability for divalent cations].

V K Lishko·E A Saĭchenko·L G Storchak·N G Gimmerl'reĭkh
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Abstract

The dependence of Ca2+ transport in synaptosomes along the channels formed by alpha-latrotoxin on [Ca2+]in and the feasibility of transport along these channels of other bivalent cations were studied. It was found that the concentration dependence of Ca2+ influx is nonlinear and is described by the Michaelis-Menten kinetics (Km = 1.07 +/- 0.19 mM). Mg2+, Ba2+, Sr2+, Mn2+ and Co2+ competitively inhibited the Ca2+ influx via latrotoxin channels. Studies with the use of the fluorescent Ca2+ probes, Quin-2 and Fura-2, revealed that these cations can also penetrate inside synaptosomes via latrotoxin channels. The bivalent cation influx via latrotoxin channels caused a decrease of the membrane potential of synaptosomes. The similarity of properties of latrotoxin and endogenous Ca2+ channels is discussed.

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AminoquinolinesBiological TransportCalciumCations, DivalentFluorescent DyesFura-2Ion ChannelsKineticsPermeabilitySpider VenomsSynaptosomesEnglish AbstractJournal Article

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V K Lishko, E A Saĭchenko, L G Storchak, N G Gimmerl'reĭkh. 1990. [Latrotoxin channels. Permeability for divalent cations].. https://pubmed.ncbi.nlm.nih.gov/1706630/

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