A sub-threshold dose of pilocarpine increases glutamine synthetase in reactive astrocytes and enhances the progression of amygdaloid-kindling epilepsy in rats.

The prognosis of patients exposed to a sub-threshold dose of a proconvulsant is difficult to establish. In this study, we investigated the effect of a single sub-threshold dose of the proconvulsant pilocarpine (PILO) on the progression of seizures that were subsequently induced by daily electrical stimulation (kindling) of the amygdaloid formation. Male Sprague–Dawley rats were each implanted with an electrode in the right basolateral amygdala and an indwelling cannula in the right ventricle.

A Transient Upregulation of Glutamine Synthetase in the Dentate Gyrus Is Involved in Epileptogenesis Induced by Amygdala Kindling in the Rat.

Reduction of glutamine synthetase (GS) function is closely related to established epilepsy, but little is known regarding its role in epileptogenesis. The present study aimed to elucidate the functional changes of GS in the brain and its involvement in epileptogenesis using the amygdala kindling model of epilepsy induced by daily electrical stimulation of basolateral amygdala in rats. Both expression and activity of GS in the ipsilateral dentate gyrus (DG) were upregulated when kindled seizures progressed to stage 4.

Reactive astrocytes contribute to increased epileptic susceptibility induced by subthreshold dose of pilocarpine.

Seizures may influence epileptogenesis, but it is not yet clearly established whether subthreshold stimulations that are not sufficient to induce visible behavioral seizures change epileptic susceptibility, and the possible underlying mechanisms have not been completely understood. We assessed the susceptibility to epilepsy after subthreshold dose of pilocarpine, as well as glial fibrillary acidic protein (GFAP) expression using immunohistochemistry. An increase in the susceptibility to pentylenetetrazole (PTZ)-induced seizures was observed in rats previously subjected to subthreshold dose of pilocarpine.

Therapeutic time window of low-frequency stimulation at entorhinal cortex for amygdaloid-kindling seizures in rats.

The present study was designed to determine whether low-frequency stimulation (LFS) of the entorhinal cortex(EC) has an anticonvulsive effect, and whether LFS delivered at different times plays different roles. We found that LFS of the EC immediately or 4 s after kindling stimulation had an anticonvulsive effect, and that the latter had a better effect on both kindling and kindled seizures. However, LFS delivered after the cessation of afterdischarge or 10 s after the kindling stimulation, augmented the epileptic activity.

Mode-dependent effect of low-frequency stimulation targeting the hippocampal CA3 subfield on amygdala-kindled seizures in rats.

Brain stimulation with low-frequency stimulation (LFS) is emerging as an alternative treatment for refractory epilepsy. The present study aimed to investigate the effects of LFS targeting the hippocampal CA3 subfield in different modes on amygdala-kindled seizures in Sprague-Dawley rats. When fully kindled seizures were achieved by daily electrical stimulation of the amygdala, LFS (15 min train of 0.

Low-frequency stimulation of the hippocampal CA3 subfield is anti-epileptogenic and anti-ictogenic in rat amygdaloid kindling model of epilepsy.

Neuromodulation with low-frequency stimulation (LFS), of brain structures other than epileptic foci, is effective in inhibiting seizures in animals and patients, whereas selection of targets for LFS requires further investigation. The hippocampal CA(3) subfield is a key site in the circuit of seizure generation and propagation. The present study aimed to illustrate the effects of LFS of the CA(3) region on seizure acquisition and generalization in the rat amygdaloid kindling model of epilepsy.

Time-dependent effect of low-frequency stimulation on amygdaloid-kindling seizures in rats.

Low-frequency stimulation (LFS) has been considered as a new option for the treatment of intractable epilepsy. The present study was designed to determine whether LFS of the kindling focus given at different time points after seizures exert different roles on kindling seizures. Our results showed that: (i) In kindling animals, LFS delivered immediately after cessation of the kindling stimulus inhibited the seizure stage during kindling acquisition, whereas LFS delivered after the cessation of afterdischarge accelerated the kindling progression to stages 1 and 2.

[Transfection of human hepatic stimulator substance gene could protect BEL-7402 cells against hepatotoxins].

Objective: To investigate protective effects of hHSS transfection against CCl4 or H2O2.

Methods: cDNA coding for hHSS was constructed into eukaryotic vector of pcDNA3.1 and transfected into BEL-7402 hepatoma cells.

[Prokaryotic expression and purification of human hepatic stimulator substance].

To explore the possibility of prokaryotic expression of human hepatic stimulator substance (hHSS), hHSS gene was inserted in the downstream of glutathion S-transferase (GST) in a pET-42a expression vector and recombinant GST-hHSS fusion protein was expressed under IPTG induction in BL-21(DE3) cells. The recombinant HSS was purified with His.Tag affinity chromatography, and its bioactivity was analyzed.