The Inhibitory Effects of Npas4 on Seizures in Pilocarpine-Induced Epileptic Rats

Abstract

To explore the effects of neuronal Per-Arnt-Sim domain protein 4 (Npas4) on seizures in pilocarpine-induced epileptic rats, Npas4 expression was detected by double-label immunofluorescence, immunohistochemistry, and Western blotting in the brains of pilocarpine-induced epileptic model rats at 6 h, 24 h, 72 h, 7 d, 14 d, 30 d, and 60 d after status epilepticus. Npas4 was localized primarily in the nucleus and in the cytoplasm of neurons. The Npas4 protein levels increased in the acute phase of seizures (between 6 h and 72 h) and decreased in the chronic phases (between 7 d and 60 d) in the rat model. Npas4 expression was knocked down by specific siRNA interference. Then, the animals were treated with pilocarpine, and the effects on seizures were evaluated on the 7th day. The onset latencies of pilocarpine-induced seizures were decreased, while the seizure frequency, duration and attack rate increased in these rats. Our study indicates that Npas4 inhibits seizure attacks in pilocarpine-induced epileptic rats.

Dynorphin activation of kappa opioid receptor protects against epilepsy and seizure-induced brain injury via PI3K/Akt/Nrf2/HO-1 pathway

“…Besides, elevation in cytokine levels, particularly, TNF-α, IL-2, and IL-6, has been implicated in the pathogenesis of epilepsy [27]. Pilocarpine-induced epilepsy in vivo exhibits most of the clinical and neuropathological characteristics of epilepsy and has been widely used in seizure research [10,24]. On the other hand, Mg 2+free physiological solution was generally used to induce epileptiform hippocampal neurons in vitro [10,28].…”

“…Rats were randomly assigned into four groups (n = 8/group): Control group, epileptic model group, LV-NC group, and LV-PDYN group. The epilepsy was induced by pilocarpine injection as previously described [24,25], with some alterations. The rats in the model group were injected intraperitoneally (i.p.)…”

“…A lentiviral vector that stably overexpressing PDYN (LV-PDYN) and a negative control lentiviral vector (LV-NC) were purchased from GenePharma (Shanghai, China). Stereotaxic intrahippocampus injection was done as previously described [24]. After the pilocarpine-induced seizure, rats were deeply anesthetized and the head of rats was fixed in a stereotaxic frame.…”

Dynorphin activation of kappa opioid receptor promotes microglial polarization toward M2 phenotype via TLR4/NF-κB pathway

“…Rats in the LV-NC group and LV-PDYN group received a stereotaxic intra-hippocampus injection of LV-NC (a negative control lentiviral vector; GeneChem, Shanghai, China) and LV-PDYN (a lentiviral vector stably overexpressing PDYN, GeneChem) respectively as previously described before the establishment of the epilepsy model [17]. The coding sequence of PDYN was amplified by RT-PCR and ligated them into the pGC-FU plasmid to produce pGC-FU-PDYN -green fluorescent protein (GFP) (LV-PDYN).…”

Protective effect of Fructus corni polysaccharide on hippocampal tissues and its relevant mechanism in epileptic rats induced by lithium chloride‑pilocarpine

“…For rats with SE lasting for 1 h, intraperitoneal administration of 10% chloral hydrate (350 mg/kg) (Sigma-Aldrich; Merck KGaA) was performed to terminate the seizure, and additional doses were administered if a poor effect was observed 30 min following the previous injection. Surviving rats would enter the quiet phase 24 h after modeling as previously described (15), the toxic stage consisted of the initial 2-4 days. Rats would suffer spontaneous epilepsy 7-20 days after modeling.…”