A subscription to JoVE is required to view this content. Sign in or start your free trial.
This report describes the methods to generate a model of temporal lobe epilepsy based on the electrical kindling of transgenic VGAT-Cre mice. Kindled VGAT-Cre mice may be useful in determining what causes epilepsy and for screening novel therapies.
It was discovered that electrical kindling of VGAT-Cre mice led to the spontaneous motor and electrographic seizures. A recent paper focused on how unique VGAT-Cre mice were used in developing spontaneous recurring seizures (SRS) after kindling and a likely mechanism - insertion of Cre into the VGAT gene - disrupted its expression and reduced GABAergic tone. The present study extends these observations to a larger cohort of mice, focusing on key issues such as how long the SRS continues after kindling and the effect of the animal's sex and age. This report describes the protocols for the following key steps: making headsets with hippocampal depth electrodes for electrical stimulation and for reading the electroencephalogram; surgery to affix the headset securely on the mouse's skull so that it does not fall off; and key details of the electrical kindling protocol such as duration of the pulse, frequency of train, duration of train, and amount of current injected. The kindling protocol is robust in that it reliably leads to epilepsy in most VGAT-Cre mice, providing a new model to test for novel antiepileptogenic drugs.
Epilepsy is a major neurological disorder with significant economic and human burdens. NINDS estimates there are 3 million Americans with epilepsy. Approximately 0.6 million of these patients have temporal lobe epilepsy (TLE)1. Unfortunately, medical treatment of TLE fails in one-third of the patients because of ineffectiveness, development of drug resistance, or intolerance to side effects2. Clearly, there is a significant need to develop novel therapies for TLE, a conclusion shared by the American Epilepsy Society Basic Science Committee, the International League Against Epilepsy Working Group for Preclinical Epilepsy ....
Animal use followed ARRIVE12 guidelines and was approved by the Animal Care and Use Committee of the University of Virginia.
1. Making headsets with two bipolar electrodes (Figure 1)
Figure 1: Key steps in EEG headset fabrication. (A
Animals
The model was originally developed using VGAT-Cre mice (Slc32a1tm2(cre)Lowl/J)13 on a mixed background. However, it has also been applied to the VGAT-Cre strain that is congenic with C57BL/6J. No difference has been observed in epilepsy that develops between the strains. Both strains express Cre recombinase under the control of the vesicular GABA transporter promoter. These mice were generated by knocking in an IRES-Cre cassette after the stop codon in the.......
This report describes a protocol where electrical kindling of mice leads to epilepsy. Since the stimulating electrode is placed in the hippocampus, this is a focal limbic epilepsy that models temporal lobe epilepsy (TLE) in patients. A critical step in this protocol is to use VGAT-Cre mice, which due to insertion of an IRES-Cre recombinase cassette in the Vgat gene, shows impaired inhibitory GABA currents11. C57BL/6 do not develop epilepsy after kindling with this protocol, although it is.......
The authors thank John Williamson for helpful discussions on this protocol. This work was supported by NIH/NINDS grant NS112549.
....Name | Company | Catalog Number | Comments |
16 Channel Extracellular Differential AC Amplifier (115V/60Hz) | AD Instruments | AM3500-115-60 | Alternate EEG amplifier |
363/CP PLUG COLLAR, PINS SLEEVE | P1 Technologies | 363SLEEVPIN0NL | For electrode holder |
Cable, 363-363 5CM - 100CM W/MESH 6TCM | P1 Technologies | 363363XXXXCM004 | mouse-to-commutator cable |
CCTV cameras Qcwox HD Sony IR LED | Sony | QC-SP316 | |
Commutator SL6C/SB (single brush) | P1 Technologies | 8BSL6CSBC0MT | formerly Plastics One, Inc. |
Current amplifier | A-M Systems | Model 2100 | |
Dental cement | Stoelting | 51459 | |
Drill bits, #75, OD 0.310" LOC 130 PT | Kyocera | 105-0210.310 | |
E363/0 SOCKET CONTACT SKEWED | P1 Technologies | 8IE3630XXXXE | pins for connector |
iBond Self Etch glue | Kulzer | CE0197 | |
MS363 PEDESTAL 2298 6 PIN WHITE | P1 Technologies | 8K000229801F | EEG headset connector |
Ohmeter | Simpson | 260 | High sensitivity |
PowerLab 16/35 and LabChart Pro | AD Instruments | PL3516/P | Alternate EEG software |
SomnoSuite | Kent Scientific Corp. | SS-01 | anesthesia unit & RightTemp monitoring |
Stereotactic drill and micromotor kit | Foredom Electric Co. | K.1070 | |
Stereotactic frame | David Kopf Instruments | Model 940 | |
Teflon-coated wire for depth electrode, OD 0.008' | A-M Systems | 791400 | |
VGAT-Cre mice on congenic C57BL/6J background | The Jackson Laboratory | 000664 |
This article has been published
Video Coming Soon
ABOUT JoVE
Copyright © 2024 MyJoVE Corporation. All rights reserved