Oe. Dellapaschoa et al., SEIZURE PATTERNS IN KINDLING AND CORTICAL STIMULATION MODELS OF EXPERIMENTAL EPILEPSY, Brain research, 770(1-2), 1997, pp. 221-227
A large number of animal models has been proposed for the evaluation o
f the anticonvulsant effect of antiepileptic drugs. Various seizure pa
tterns are produced and differences are frequently observed in anticon
vulsant effect estimates obtained for the same drug in different model
s. The incidence of seizures and the threshold for the induction are u
sually the only measures used for the determination of the anticonvuls
ant effect. However, behavioural components expressed during seizures
induced by different means are likely to differ considerably. The aim
of this study was to provide a detailed behavioural description of ict
al and post-ictal components in two models of electrically induced sei
zure activity: kindling and cortical stimulation model (CSM). Seizure
activity was induced in two groups of 6 Wistar-derived rats. Ictal and
post-ictal behaviours were recorded on video tape and quantified usin
g a computer supported frame-by-frame encoding of the behavioural comp
onents. We encoded the duration and rate of occurrence of the followin
g behavioural items: whisker movements, eye closure, myoclonic jerk, f
acial gasping, forelimb clonus, forelimb tonus, hindlimb tonus, immobi
lity and chewing. It appears that both models are, in many respects, q
ualitatively similar. However, the models differ quantitatively. Behav
ioural expression of seizure activity differs in the following respect
s: (1) the total duration of the seizure induced by cortical stimulati
on is shorter than by kindling; (2) seizure activity in the CSM occurs
mainly during stimulation, while in amygdala kindling, it occurs ther
eafter; and (3) seizures evoked in the CSM comprise relatively less vi
olent behavioural items than in the amygdala kindling. The evaluation
of the ictal and post-ictal behavioural components suggests that behav
ioural analysis could assist in the detection of differences in the me
chanisms of action of antiepileptic drugs. In addition, observational
measures can also be used to assess animal distress inflicted by diffe
rent experimental procedures. (C) 1997 Elsevier Science B.V.