Chemoconvulsant Model of Chronic Spontaneous Seizures

Jennifer L. Hellier1, F. Edward Dudek2

1 University of Colorado Health Sciences Center, Denver, Colorado, 2 Colorado State University, Fort Collins, Colorado
Publication Name:  Current Protocols in Neuroscience
Unit Number:  Unit 9.19
DOI:  10.1002/0471142301.ns0919s31
Online Posting Date:  May, 2005
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Animal models of injury‐induced epilepsy may provide insight into the mechanisms of acquired epilepsy. Previous animal models of temporal lobe epilepsy (TLE) were produced by acute treatments that often have high mortality rates and/or are associated with a low proportion of animals developing spontaneous, chronic motor seizures. In this unit, a protocol is provided for inducing chronic epilepsy in rats using multiple, low‐dose, intraperitoneal injections of an excitotoxic agent, kainic acid. This protocol reliably induces TLE in nearly all treated rats (97% had at least two observed spontaneous motor seizures) with a relatively low mortality rate (<15%). This modified chemoconvulsant treatment protocol (i.e., multiple low doses) is efficient and relatively simple, and the properties of the chronic epileptic state appear similar to those of severe human TLE.

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Table of Contents

  • Basic Protocol 1: Kainate Induction of Chronic Spontaneous Seizures in Rats
  • Reagents and Solutions
  • Commentary
  • Literature Cited
  • Figures
  • Tables
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Basic Protocol 1: Kainate Induction of Chronic Spontaneous Seizures in Rats

  • Male Sprague‐Dawley rats, 180 to 250 g (Harlan)
  • Tattoo dye (approved for animals) or ear‐piercing tool, optional
  • 2.5 mg/ml kainic acid in 0.9% (w/v) NaCl (see recipe)
  • 0.9% (w/v) NaCl (sterile saline)
  • Lactated Ringer's solution, 35°C
  • Apple slices and/or mashed rat chow
  • Animal scale
  • 35°C water bath or incubator
  • Standard rat cages (∼43‐cm length × 22‐cm width × 20‐cm height), with plastic lids approved by the Association for Assessment and Accreditation of Laboratory Animal Care (AAALAC; e.g., Allentown Caging)
  • Disposable bed liners and/or paper towels
  • Syringes and needles suitable for intraperitoneal and subcutaneous injections
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Literature Cited

Literature Cited
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