Computer simulation of free Ca^<2+> and synaptic plasticity at the presynaptic terminal of frog neuromuscular junction
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منابع مشابه
Endocytosis of synaptic vesicle membrane at the frog neuromuscular junction
Frog nerve-muscle preparations were quick-frozen at various times after a single electrical stimulus in the presence of 4-aminopyridine (4-AP), after which motor nerve terminals were visualized by freeze-fracture. Previous studies have shown that such stimulation causes prompt discharge of 3,000-6,000 synaptic vesicles from each nerve terminal and, as a result, adds a large amount of synaptic v...
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Frog cutaneous pectoris muscles were treated with low doses of crude black widow spider venom (BWSV) or purified alpha-latrotoxin, and neuromuscular transmission, quantal secretion, changes in ultrastructure and uptake of horseradish peroxidase (HRP) were studied. When these agents were applied to muscles bathed in a Ca2+-free solution with 1 mM EGTA and 4 mM Mg2+, the rate of quantal secretion...
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We have characterized the morphological and functional properties of the readily releasable pool (RRP) and the reserve pool of synaptic vesicles in frog motor nerve terminals using fluorescence microscopy, electron microscopy, and electrophysiology. At rest, about 20% of vesicles reside in the RRP, which is depleted in about 10 s by high-frequency nerve stimulation (30 Hz); the RRP refills in a...
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The ability of perisynaptic glial cells to modulate transmitter release and synaptic depression was studied at the frog neuromuscular junction (nmj). Injection of GTPgammaS in perisynaptic Schwann cells (PSCs), glial cells at this synapse, induced a reduction in the amplitude of nerve-evoked synaptic responses but had no effect on the frequency, the amplitude, or the duration of the miniature e...
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Ca2+ indicators of varying affinity and mobility were pressure injected into the presynaptic axon of the inhibitor of the crayfish neuromuscular junction (NMJ). Fluorescence transients recorded at a 2-kHz resolution were used to probe physiological parameters governing the decay of fluorescence transients within 100 ms after an action potential (early decay). Blocking Ca2+ extrusion or Ca2+ seq...
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ژورنال
عنوان ژورنال: Seibutsu Butsuri
سال: 1999
ISSN: 0582-4052,1347-4219
DOI: 10.2142/biophys.39.s52_3