Name: the pilocarpine model of temporal lobe epilepsy and eeg monitoring using radiotelemetry system in mice
Uploaded: 2018-02-27T13:30:00
Description: Watch this Scientific Journal Video about The Pilocarpine Model of Temporal Lobe Epilepsy and EEG Monitoring Using Radiotelemetry System in Mice at JoVE.com

This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean Government (NRF-2014R1A1A3049456) and a grant from the Korea Health Technology R&amp;D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health &amp; Welfare, Republic of Korea (HI15C2854).

All experimental procedures were approved by the Ethics Committee of the Catholic University of Korea and were carried out in accordance with the National Institutes of Health Guide for the Care and Use of Laboratory Animals (NIH Publications No. 80-23).
1. SE Induction
<ol>
	<li>Purchase 8-week-old male C57BL/6NHsd mice and weigh each mouse. Then, use a marker pen to mark the tails of all mice for their easy identification during SE induction.</li>
	<li>Calculate the amount of scopolamine m...

<ol>
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N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pilocarpine-induced+status+epilepticus+results+in+mossy+fiber+sprouting+and+spontaneous+seizures+in+C57BL/6+and+CD-1+mice.">Pilocarpine-induced status epilepticus results in mossy fiber sprouting and spontaneous seizures in C57BL/6 and CD-1 mice.</a> Epilepsy Research. 49 (2), 109-120 (2002).</li><li>Borges, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neuronal+and+glial+pathological+changes+during+epileptogenesis+in+the+mouse+pilocarpine+model.">Neuronal and glial pathological changes during epileptogenesis in the mouse pilocarpine model.</a> Exp Neurol. 182 (1), 21-34 (2003).</li><li>Pavlova, M. K., Shea, S. A., Bromfield, E. 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This work describes the experimental procedures for the SE induction and the evaluation of chronic seizures.
Several factors can affect successful SE induction. Accurate behavioral monitoring according to the Racine scale is critical for the development of SRS. Head nodding, forelimb clonus, rearing, and falling are the behavioral hallmarks of acute seizures developing into SE phase4,16. Once the first motor seizure is detected, the le...

TLE is one of the most common acquired epilepsies1. People with epilepsy experience recurrent seizures as a result of abnormal neuronal activities in the brain2,3. Given that TLE is often intractable, it is crucial to understand the basic mechanisms underlying the development of epilepsy.
Animal models that can recapitulate the key characteristics of human TLE can offer better appreciation of TLE pathophysiology, allowing us to readily monitor and manipulate critical factors in epileptogenesis. Among them, chemoconvulsants-induced SE has been widely used4,5. Unlike other epilepsy models, such as electrical stimulation which shows no hippocampal sclerosis and robust SRS6,7,8, the systemic injection of chemoconvulsants can mimic clinical pathogenesis of human TLE, i.e., initial brain injury, a latent period, and a chronic epileptic stage manifesting SRS5,9,10. Therefore, this technique can be utilized in various studies explaining the mechanisms of acute brain damage, epileptogenesis, or seizure suppression. Moreover, histopathological alterations induced by chemoconvulsants are similar to those seen in human TLE, providing an additional rationale for use of TLE rodent models10,11,12. Notably, structural damages involving the hippocampus have been consistently reproduced in both kainic acid- and pilocarpine-induced SE models. However, compared to kainic acid injection, the pilocarpine model can produce more robust SRS in mice, which can offer sizable advantages for studying chronic epilepsy when considering the wide availability of transgenic mouse lines5,13,14,15. Moreover, seizure progression after pilocarpine injection is generally faster than in the kainic acid model, providing additional evidence for the effective use of a pilocarpine model of epilepsy.
Here, we demonstrate a method of inducing SE by the i.p. injection of pilocarpine and by performing video and EEG monitoring in chronic epilepsy.

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			<td height="40" style="height:40px;width:189px;">C57BL/6</td>
			<td style="width:233px;">Envigo</td>
			<td style="width:175px;">C57BL/6NHsd</td>
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			<td height="40" style="height:40px;">Scopolamine methyl nitrate</td>
			<td>Sigma</td>
			<td>S2250</td>
			<td>Make 10X stock</td>
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			<td height="40" style="height:40px;">Terbutaline hemisulfate salt</td>
			<td>Sigma</td>
			<td>T2528</td>
			<td>Make 10X stock</td>
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			<td height="40" style="height:40px;">Pilocarpine hydrochloride</td>
			<td>Sigma</td>
			<td>P6503</td>
			<td></td>
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			<td height="40" style="height:40px;">Intensive care unit</td>
			<td>Daejong instrument industry Co., Ltd.</td>
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			<td>28~30&#8451;&#160;</td>
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			<td>Yuhan corporation</td>
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			<td height="40" style="height:40px;">Xylazine hydrochloride</td>
			<td>Bayer Korea</td>
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			<td>SAMJIN</td>
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			<td height="40" style="height:40px;">Castor oil (Kolliphor EL)</td>
			<td>Sigma</td>
			<td>C5135</td>
			<td>Polyoxyl 35 hydrogenated castor oil</td>
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			<td height="40" style="height:40px;">Saline</td>
			<td>Daihan pharm. Co.</td>
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			<td></td>
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			<td height="40" style="height:40px;">5% Dextrose</td>
			<td>Daihan pharm. Co.</td>
			<td></td>
			<td></td>
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			<td height="40" style="height:40px;">Iodine solution (Povidin)</td>
			<td>Firson</td>
			<td></td>
			<td></td>
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			<td height="40" style="height:40px;">vet ointment (Terramycin)</td>
			<td>Pfizer</td>
			<td></td>
			<td></td>
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		<tr height="40">
			<td height="40" style="height:40px;">Blue Nylon</td>
			<td>AILEE</td>
			<td>NB617</td>
			<td></td>
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		<tr height="40">
			<td height="40" style="height:40px;">Mupirocin (Bearoban)</td>
			<td>Daewoong Pharmaceutical Co., Ltd</td>
			<td></td>
			<td></td>
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			<td height="40" style="height:40px;">Ketoprofen</td>
			<td>Samchundang Pharm. Co., Ltd</td>
			<td></td>
			<td>5 mg/kg</td>
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		<tr height="40">
			<td height="40" style="height:40px;">Gentamicin</td>
			<td>Huons, Ltd.</td>
			<td></td>
			<td>5 mg/kg</td>
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			<td height="40" style="height:40px;">1 mL syringe</td>
			<td>Sung shim medial Co., Ltd.</td>
			<td></td>
			<td></td>
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			<td height="40" style="height:40px;">26 guage needle</td>
			<td>Sung shim medial Co., Ltd.</td>
			<td></td>
			<td>26 G * 13 mm (1/2&#34;)</td>
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			<td height="40" style="height:40px;">30 guage needle</td>
			<td>Sung shim medial Co., Ltd.</td>
			<td></td>
			<td>30 G * 13 mm (1/2&#34;)</td>
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			<td height="40" style="height:40px;">Razor blade</td>
			<td>Dorco</td>
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			<td></td>
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			<td height="40" style="height:40px;">Drill</td>
			<td>Saeshin precision Co., Ltd.</td>
			<td></td>
			<td>207A, 35K (speed)</td>
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			<td height="40" style="height:40px;">Telemetry video/EEG system</td>
			<td>Data sciences International. Inc.</td>
			<td>Version 5.20-SP6</td>
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			<td height="40" style="height:40px;">Implantable transmitter</td>
			<td>Data sciences International. Inc.</td>
			<td>ETA-F10</td>
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			<td height="40" style="height:40px;">Screw</td>
			<td>Sungho Steel</td>
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			<td>M1.4, 2 mm length stainless steel</td>
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			<td height="40" style="height:40px;">Vertex dental material&#160;</td>
			<td>Dentimex</td>
			<td></td>
			<td></td>
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			<td height="40" style="height:40px;">Acetone</td>
			<td>Duksan pure chemicals Co., Ltd.</td>
			<td></td>
			<td>CAS 67-64-1</td>
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			<td height="40" style="height:40px;">Paraformaldehyde (PFA)</td>
			<td>millipore</td>
			<td>1.04005.1000</td>
			<td>4 %&#160;</td>
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			<td height="40" style="height:40px;">Sucrose</td>
			<td>Sigma</td>
			<td>S9378</td>
			<td>30 % solution in 0.01 M PBS</td>
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			<td height="40" style="height:40px;">Cresyl violet acetate</td>
			<td>Sigma</td>
			<td>C5042</td>
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			<td height="40" style="height:40px;">Ethanol</td>
			<td>EMD Millipore Co.</td>
			<td>UN1170</td>
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			<td height="40" style="height:40px;">xylene</td>
			<td>Duksan pure chemicals Co., Ltd.</td>
			<td>UN1307</td>
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			<td height="40" style="height:40px;">Acetic acid glacial</td>
			<td>Junsei chemical</td>
			<td>31010-0350</td>
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			<td height="40" style="height:40px;">FSC33 Clear&#160;</td>
			<td>Leica biosystems</td>
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			<td>OCT compound for tissue freezing</td>
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			<td height="40" style="height:40px;">DPX Mounting for histology</td>
			<td>Sigma</td>
			<td>6522</td>
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			<td height="40" style="height:40px;">Forceps</td>
			<td>Fine science tools</td>
			<td>11002-12</td>
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			<td height="40" style="height:40px;">Scissors</td>
			<td>Solco biomedical</td>
			<td>02-2445</td>
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			<td height="38" style="height:38px;">Stereotaxic frame</td>
			<td>David Kopf Instruments</td>
			<td>E51070012</td>
			<td></td>
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the pilocarpine model of temporal lobe epilepsy and eeg monitoring using radiotelemetry system in mice

Temporal lobe epilepsy (TLE) is a common neurological disorder in adulthood. For translational studies of chronic epilepsy, pilocarpine-induced status epilepticus (SE) is frequently selected to recapitulate spontaneous recurrent seizures (SRS). Here we present a protocol of SE induction by intraperitoneal (i.p.) injection of pilocarpine and monitoring of chronic recurring seizures in live animals using a wireless telemetry video and electroencephalogram (EEG) system. We demonstrated notable behavioral changes that need attention after pilocarpine injection and their correlation with hippocampal neuronal loss at 7 days and 6 weeks post-pilocarpine. We also describe the experimental procedures of electrode implantation for video and EEG recording, and analysis of the frequency and duration of chronic recurrent seizures. Finally, we discuss the possible reasons why the expected results are not achieved in each case. This provides a basic overview of modeling chronic epilepsy in mice and guidelines for troubleshooting. We believe this protocol can serve as a baseline for suitable models of chronic epilepsy and epileptogenesis.

Successful SE can induce hippocampal cell death and SRS (Figure 1 and Figure 2). We terminated behavioral acute seizures by diazepam injection at 3 h after SE onset and sacrificed the mice 7 days or 6 weeks later.
For video-EEG monitoring, the mice received implant surgery at 4 weeks after SE, and SRS cases were evaluated for 2 weeks from 5-7 weeks after SE onset.
<...

Watch this Scientific Journal Video about The Pilocarpine Model of Temporal Lobe Epilepsy and EEG Monitoring Using Radiotelemetry System in Mice at JoVE.com

The Pilocarpine Model of Temporal Lobe Epilepsy and EEG Monitoring Using Radiotelemetry System in Mice

This manuscript describes a method of inducing status epilepticus by systemic pilocarpine injection and of monitoring spontaneous recurrent seizures in live animals using a wireless telemetry video and electroencephalogram system. This protocol can be utilized for studying the pathophysiologic mechanisms of chronic epilepsy, epileptogenesis, and acute seizures.

Temporal lobe epilepsy (TLE) is a common neurological disorder in adulthood. For translational studies of chronic epilepsy, pilocarpine-induced status ...

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