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Long-term sensitization training in Aplysia decreases the excitability of a decision-making neuron through a sodium-dependent mechanism.

ABSTRACT: In Aplysia, long-term sensitization (LTS) occurs concurrently with a suppression of feeding. At the cellular level, the suppression of feeding is accompanied by decreased excitability of decision-making neuron B51. We examined the contribution of voltage-gated Na⁺ and K⁺ channels to B51 decreased excitability. In a pharmacologically isolated Na⁺ channels environment, LTS training significantly increased B51 firing threshold, compared with untrained controls. Conversely, in a pharmacologically isolated K⁺ channels environment, no differences were observed between trained and untrained animals in either amplitude or area of B51 K⁺-dependent depolarizations. These findings suggest that Na⁺ channels contribute to the decrease in B51 excitability induced by LTS training.

SUBMITTER: Hernandez JS

PROVIDER: S-EPMC5435880 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Long-term sensitization training in Aplysia decreases the excitability of a decision-making neuron through a sodium-dependent mechanism.

Hernandez John S JS Wainwright Marcy L ML Mozzachiodi Riccardo R

Learning & memory (Cold Spring Harbor, N.Y.) 20170515 6

In Aplysia, long-term sensitization (LTS) occurs concurrently with a suppression of feeding. At the cellular level, the suppression of feeding is accompanied by decreased excitability of decision-making neuron B51. We examined the contribution of voltage-gated Na+ and K+ channels to B51 decreased excitability. In a pharmacologically isolated Na+ channels environment, LTS training significantly increased B51 firing threshold, compared with untrained control ...[more]

PMID: 28507035

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