Changes in Functional Properties of Rat Hippocampal Neurons Following Pentylenetetrazole-induced Status Epilepticus

Publication date: Available online 26 December 2018Source: NeuroscienceAuthor(s): Tatyana Y. Postnikova, Dmitry V. Amakhin, Alina M. Trofimova, Ilya V. Smolensky, Aleksey V. ZaitsevAbstractPathophysiological remodeling processes following status epilepticus (SE) play a critical role in the pathophysiology of epilepsy but have not yet been not fully investigated. In the present study, we examined changes in intrinsic properties of pyramidal neurons, basal excitatory synaptic transmission, and short-term synaptic plasticity in hippocampal slices of rats after SE. Seizures were induced in 3-week-old rats by an intraperitoneal pentylenetetrazole (PTZ) injection. Only animals with generalized seizures lasting more than 30 min were included in the experiments. We found that CA1 pyramidal neurons became more excitable and started firing at a lower excitatory input due to a significant increase in input resistance. However, basal excitatory synaptic transmission was reduced in CA3-CA1 synapses, thus preventing the propagation of excitation through neural networks. A significant increase in paired-pulse facilitation 1 d after SE pointed to a decrease in the probability of glutamate release. Increased intrinsic excitability of neurons and decreased synaptic transmission differentially affected the excitability of a neural network. In terms of changes in seizure susceptibility after SE, we observed a significant increase in the maximal electroshock threshold 1 day after SE, sugges...
Source: Neuroscience - Category: Neuroscience Source Type: research