Dependence of synaptic facilitation postsynaptically induced in snail neurones on season and serotonin level.
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.
Malyshev
A
A
Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia.
Bravarenko
N
N
Balaban
P
P
D000818:Animals; D005071:Evoked Potentials / Q000502:physiology; D006185:Habituation, Psychophysiologic / Q000502:physiology; D006372:Helix, Snails; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000378:metabolism / Q000502:physiology*; D012621:Seasons; D012701:Serotonin / Q000378:metabolism*; D009435:Synaptic Transmission / Q000502:physiology*
D012701:Serotonin