[Calcium permeability of synaptosomes induced by alpha-latrotoxin].
The paper deals with characteristics of ionic alpha-latrotoxin-induced permeability of rat brain synaptosomes. It has been shown that the addition of alpha-latrotoxin to synaptosomes in the Ca2+-containing media resulted in an extensive and rapid uptake of 45Ca2+ in synaptosomes. alpha -Latrotoxin was not able to enhance the 22Na+ and 86Rb+ uptake or efflux in the Ca2+-containing and Ca2+- and Mg2+-free media. The dye di-O-C3 was used to monitor the membrane potential changes as a consequence of alpha-latrotoxin treatment of synaptosomes. It has been found that alpha-latrotoxin increased synaptosomal fluorescence in the Ca2+-containing media, but failed to induce any increase of fluorescence in Ca2+- and Mg2+-free media. It has been also shown that the calcium uptake induced by alpha-latrotoxin depends on free calcium concentration in synaptosomes. Toxin-induced calcium flows are shown to be of the vector character.
D000818:Animals; D001180:Arthropod Venoms / Q000494:pharmacology*; D001692:Biological Transport / Q000187:drug effects; D001921:Brain / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D002463:Cell Membrane Permeability / Q000187:drug effects; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects*; D007700:Kinetics; D051381:Rats; D013111:Spider Venoms / Q000494:pharmacology*; D013570:Synaptic Membranes / Q000378:metabolism; D013574:Synaptosomes / Q000378:metabolism*
D001180:Arthropod Venoms; D007473:Ion Channels; D013111:Spider Venoms; C020763:alpha-latrotoxin; D002118:Calcium
O kal'tsievoĭ pronitsaemosti sinaptosom, indutsirovannoĭ alpha-latrotoksinom.