Contribution of histone acetylation to the serotonin-mediated long-term synaptic plasticity in terrestrial snails

Abstract

Serotonin plays a decisive role in long-term synaptic plasticity and long-term memory in mollusks.Previously, we demonstrated that histone acetylation is a critical regulatory mechanism of long-term memory in terrestrial snail. At the behavioral level, many studies were done in Helix to elucidate the role of histone acetylation and serotonin. However, the impact of histone acetylation on long-term potentiation of synaptic e ciency in electrophysiological studies in Helix has been studied only in one paper. Here we investigated effects of serotonin, histone deacetylases inhibitors sodium butyrate and trichostatin A, and a serotonergic receptor inhibitor methiothepin on long-term potentiation of synaptic responses in vitro. We demonstrated that long-term potentiation was suppressed by methiothepin but rescued by coapplication of histone deacetylase inhibitors sodium butyrate or trichostatin A. Increased histone acetylation compensated the loss of serotonergic activation. We showed that single serotonin application in combination with histone deacetylase blockade could mimic the effect of repeated serotonin applications and be enough for sustained long-lasting synaptic changes. The data obtained demonstrated that histone deacetylases blockade ameliorated de cits in synaptic plasticity induced by different paradigms (methiothepin treatment, the weak training protocol with single application of serotonin), suggesting that histone acetylation contributes to the serotonin-mediated synaptic plasticity.

Hormonal computing: a conceptual approach

“…The EES triggers the neuronal activity of the spinal cord segment to compensate for the lack of electrical activity from the brain. Active substances including quipazine facilitate the sensory input of the afferents ( Gad et al, 2013) and accelerate the learning processes, enhancing the receptor trafficking to synapses ( Zuzina et al, 2019 ; Zuzina and Balaban, 2022 ). During the influence of active substances, the stimulation of the limbs is generated in the walking pattern ( Gad et al, 2013) .…”