Changes in excitability of a command neuron in the initial period of conditioning in Helix pomatia

Litvinov, E G; Logunov, D. B.

doi:10.1007/bf01195528

Cited by 3 publications

(6 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It was shown, that food-aversion learning results in significant increase of synaptic response of withdrawal command neurons to a particular type of food presentation, thus evoking the spike discharge and corresponding withdrawal [17]. Besides this, during formation of avoidance reflexes, including food aversion, an excitability and the amount of bound calcium changes in command neurons [27], [28], [29], [30]. Previously we found that in the case of food avoidance learning of adult Helix , following 15 minutes training, there is a significant activation of MAPK/ERK kinase and histone H3 acetylation in command neurons of the left, but not right parietal ganglion [21], [23].…”

Section: Discussionmentioning

confidence: 99%

Failure of Long-Term Memory Formation in Juvenile Snails Is Determined by Acetylation Status of Histone H3 and Can Be Improved by NaB Treatment

Danilova

Grinkevich

2012

PLoS ONE

View full text Add to dashboard Cite

BackgroundAnimals’ capacities for different forms of learning do not mature simultaneously during ontogenesis but the molecular mechanisms behind the delayed development of specific types of memory are not fully understood. Mollusks are considered to be among the best models to study memory formation at the molecular level. Chromatin remodeling in developmental processes, as well as in long-term memory formation, was recently shown to play a major role. Histone acetylation is a key process in the chromatin remodeling and is regulated through the signaling cascades, for example MAPK/ERK. Previously, we found that MAPK/ERK is a key pathway in the formation of the food aversion reflex in Helix. Pretreatment with upstream ERK kinase inhibitor PD98059 prevented food avoidance learning in adult Helix. In contrast to adult snails, juveniles possess immature plasticity mechanisms of the avoidance reflex until the age of 2–3 months while the MAPK/ERK cascade is not activated after aversive learning. In the present study, we focused on the potential MAPK/ERK target - histone H3.Methodology/Principal FindingsHere we found that a significant increase in histone H3 acetylation occurs in adult animals after learning, whereas no corresponding increase was observed in juveniles. The acetylation of histone H3 is regulated by ERK kinase, since the upstream ERK kinase inhibitor PD98059 prevented the increase of histone H3 acetylation upon learning. We found that the injection of histone deacetylase inhibitor sodium butyrate (NaB) prior to training led to induction in histone H3 acetylation and significantly ameliorated long-term memory formation in juvenile snails.Conclusions/SignificanceThus, MAPK/ERK-dependent histone H3 acetylation plays an essential role in the formation of food aversion in Helix. Dysfunction of the MAPK/ERK dependent histone H3 acetylation might determine the deficiency of avoidance behavior and long-term plasticity in juvenile animals. Stimulation of histone H3 acetylation in juvenile animals by NaB promoted avoidance plasticity.

show abstract

Section: Discussionmentioning

confidence: 99%

Failure of Long-Term Memory Formation in Juvenile Snails Is Determined by Acetylation Status of Histone H3 and Can Be Improved by NaB Treatment

Danilova

Grinkevich

2012

PLoS ONE

View full text Add to dashboard Cite

show abstract

“…The use of semi-intact preparations provides significantly greater possibilities for studying the membrane mechanisms of plasticity, because the preserved connections mean that not only analogs of signals but the signals themselves can be investigated [8,10,17]. However, the best results are obtained using trained animals [2,6,9,10,14,22].…”

Section: Discussionmentioning

confidence: 99%

“…On the day after LTS or DCR formation was completed, the electrical characteristics of the defensive behavior command neurons LPa3, RPa3, LPa2, and RPa2 was recorded, as well as those of motor neurons involved in opening and closing the pneumostoma [2,8]. These command neurons are located in the left and right parietal ganglia, and the motoneurons are located in the visceral ganglion.…”

Section: Methodsmentioning

confidence: 99%

“…Many studies have been performed on mollusks, which have relatively simple nervous systems with identified cellular elements and quite complex behavior [6,10,11,14,22]. Thus, associative training of the common snail was accompanied by increases in the excitability of command neurons LPa3 and RPa3--with appearance of action potentials after 25-30 combinations of the conditioned and unconditioned stimuli [8] and generation of large numbers of action potentials after acquisition of the conditioned reflex [9]. Thus, associative training of the common snail was accompanied by increases in the excitability of command neurons LPa3 and RPa3--with appearance of action potentials after 25-30 combinations of the conditioned and unconditioned stimuli [8] and generation of large numbers of action potentials after acquisition of the conditioned reflex [9].…”

mentioning

confidence: 99%

See 1 more Smart Citation

The electrical characteristics of command and motor neurons during acquisition of a conditioned defensive reflex and formation of long-term sensitization in snails

Kl¹,

Vv²,

Tk³

et al. 2000

Neurosci Behav Physiol

View full text Add to dashboard Cite

The mechanisms of the acquisition of a conditioned defensive reflex and formation of long-term sensitization were studied at the level of an analysis of the electrical characteristics of defensive behavior command neurons and motor neurons which open and close the pneumostoma. Significant decreases in membrane and threshold potentials were seen in command neurons in response to acquisition of the conditioned defensive reflex and formation of long-term sensitization, along with further decreases in these parameters in snails which were trained after long-term sensitization. Changes in the critical level of depolarization and amplitude of action potentials were insignificant. The changes observed here provide evidence for an increase in the membrane excitability of command neurons. Similar changes were not seen in motor neurons.

show abstract

“…Another possible explanation for neuronal plasticity is a change in the properties of the excitable membrane [322,350,393] that is not completely consistent with the all-or-none principle [227]. Excitability usually increases [202,354,395] during augmentation of the biological importance of the signal and decreases [326,358,361] when it falls. This simple rule holds true for classical conditioning, habituation, dishabituation, and extinction.…”

Section: Single Neurons Can Learnmentioning

confidence: 99%

Protection from neuronal damage evoked by a motivational excitation is a driving force of intentional actions

Tsitolovsky

2005

Brain Research Reviews

View full text Add to dashboard Cite

Changes in excitability of a command neuron in the initial period of conditioning in Helix pomatia

Cited by 3 publications

References 4 publications

Failure of Long-Term Memory Formation in Juvenile Snails Is Determined by Acetylation Status of Histone H3 and Can Be Improved by NaB Treatment

Failure of Long-Term Memory Formation in Juvenile Snails Is Determined by Acetylation Status of Histone H3 and Can Be Improved by NaB Treatment

The electrical characteristics of command and motor neurons during acquisition of a conditioned defensive reflex and formation of long-term sensitization in snails

Protection from neuronal damage evoked by a motivational excitation is a driving force of intentional actions

Contact Info

Product

Resources

About