Extract Depresses Excitatory Synaptic Transmission and Chemically-Induced Seizures in the Rat Hippocampus

Overview

Journal Front Pharmacol

Date 2021 Mar 25

PMID 33762938

Authors

Patrick Amoateng

Thomas A Tagoe

Thomas K Karikari

Kennedy K E Kukuia

Dorcas Osei-Safo

Eric Woode

Bruno G Frenguelli

Samuel B Kombian

Affiliations

Soon will be listed here.

Abstract

Extracts of the tropical Cinderella plant are used traditionally to manage convulsive conditions in the West African sub-region. This study sought to determine the neuronal basis of the effectiveness of these plant extracts to suppress seizure activity. Using the hippocampal slice preparation from rats, the ability of the extract to depress excitatory synaptic transmission and seizure activity were investigated. Bath perfusion of the hydro-ethanolic extract of (SNE) caused a concentration-dependent depression of evoked field excitatory postsynaptic potentials (fEPSPs) recorded extracellularly in the CA1 region of the hippocampus with maximal depression of about 80% and an estimated IC of 0.06 mg/ml. The SNE-induced fEPSP depression was accompanied by an increase in paired pulse facilitation. The fEPSP depression only recovered partially after 20 min washing out. The effect of SNE was not stimulus dependent as it was present even in the absence of synaptic stimulation. Furthermore, it did not show desensitization as repeat application after 10 min washout produced the same level of fEPSP depression as the first application. The SNE effect on fEPSPs was not via adenosine release as it was neither blocked nor reversed by 8-CPT, an adenosine A receptor antagonist. In addition, SNE depressed seizures induced by zero Mg and high K -containing artificial cerebrospinal fluid (aCSF) in a concentration-dependent manner. The results show that SNE depresses fEPSPs and spontaneous bursting activity in hippocampal neurons that may underlie its ability to abort convulsive activity in persons with epilepsy.

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