title: Modulation of defensive reflex conditioning in snails by serotonin.
abstract: Highlights Daily injection of serotonin before a training session accelerated defensive reflex conditioning in snails.Daily injection of 5-hydroxytryptophan before a training session in snails with a deficiency of serotonin induced by the "neurotoxic" analog of serotonin 5,7-dihydroxytryptamine, restored the ability of snails to learn.After injection of the "neurotoxic" analogs of serotonin 5,6- and 5,7-dihydroxytryptamine as well as serotonin, depolarization of the membrane and decrease of the threshold potential of premotor interneurons was observed. We studied the role of serotonin in the mechanisms of learning in terrestrial snails. To produce a serotonin deficit, the "neurotoxic" analogs of serotonin, 5,6- or 5,7-dihydroxytryptamine (5,6/5,7-DHT) were used. Injection of 5,6/5,7-DHT was found to disrupt defensive reflex conditioning. Within 2 weeks of neurotoxin application, the ability to learn had recovered. Daily injection of serotonin before a training session accelerated defensive reflex conditioning and daily injections of 5-HTP in snails with a deficiency of serotonin induced by 5,7-DHT restored the snail's ability to learn. We discovered that injections of the neurotoxins 5,6/5,7-DHT as well as serotonin, caused a decrease in the resting and threshold potentials of the premotor interneurons LPa3 and RPa3.
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia ; Group of Biophysics, Zavoisky Physical-Technical Institute, Russian Academy of Sciences Kazan, Russia.
authors.forename: Vyatcheslav V
authors.initials: VV
authors.lastname: Andrianov
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia ; Department of Biomedical Sciences, Volga Region State Academy of Physical Culture, Sport and Tourism Kazan, Russia.
authors.forename: Tatiana K
authors.initials: TK
authors.lastname: Bogodvid
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia.
authors.forename: Irina B
authors.initials: IB
authors.lastname: Deryabina
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia.
authors.forename: Aleksandra N
authors.initials: AN
authors.lastname: Golovchenko
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia.
authors.forename: Lyudmila N
authors.initials: LN
authors.lastname: Muranova
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia.
authors.forename: Roza R
authors.initials: RR
authors.lastname: Tagirova
authors.affiliation: Laboratory of Cellular Neurobiology of Learning, Institute of High Nerve Activity and Neurophysiology, Russian Academy of Sciences Moscow, Russia.
authors.forename: Aliya K
authors.initials: AK
authors.lastname: Vinarskaya
authors.affiliation: Laboratory of Neurobiology, Institute of Fundamental Medicine and Biology, Kazan Federal University Kazan, Russia ; Group of Biophysics, Zavoisky Physical-Technical Institute, Russian Academy of Sciences Kazan, Russia.
authors.forename: Khalil L
authors.initials: KL
authors.lastname: Gainutdinov
keywords: associative learning; identified neurons; membrane potential; serotonin; snail; threshold potential