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Dependence of synaptic facilitation postsynaptically induced in snail neurones on season and serotonin level
A Malyshev1, N Bravarenko, P Balaban
1Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia.
Abstract:
The problem of stability of long-lasting synaptic facilitation postsynaptically induced by intracellular current pulses without concomitant presynaptic activation was addressed. A short (15-20 min) phase of synaptic facilitation induced by intracellular tetanization in identified snail neurones was stable and present in all experiments, while a long-term phase (lasting > or = 50 min) was observed only some experiments. Data analysis revealed dependence of the long-term phase on season. Dependence of the long-term phase of facilitation on serotonin concentration in hemolymph, which is known to change with season, was shown using the selective neurotoxin 5,7-dihydroxytriptamine. Dependence of habituation rate in the same synaptic connection on season and serotonin level was shown.
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