Introduction. With the aim of chronic epilepsy induced cognitive disturbances investigations it is necessary to develop experimental models, which are able to develop pathogenetic manifestations corresponded to clinician symptoms.
Aim of investigation was confined to identification of pentylenetetrazol (PTZ)-induced kindling as a model of cognitive disturbances via investigation of the pronouncement of conditioned avoiding reactions (CAR) both at early and postponed phases of kindling.
Methods of investigations. Kindling was induced in Wistar rats through PTZ administrations in subthreshold dosage (30.0 mg/kg, i. p.) during three weeks. CAR have been worked out via 30 times influences upon rat with conditioned (noise signal) and not-conditioned (electric shock), which have been performed daily during four days. The number of CAR as well as the latency of avoidance have been taking into consideration as informative indices.
Results of investigations. The number of CAR, which have been registered at the early stage of kindling (24 hr from the moment of the last kindled epileptogen administration) have been reduced by 43.5% (р<0.05) when compared with the initial value, registered before first PTZ administration (р<0.05). At the same time number of CAR was by 29.1% less when compared with the control group of rats (р<0.05). The latency of CAR exceeded that one before kindling by 19.1% (р<0.05). In postponed period of kindling (two weeks from the moment of kindling induction and 10 days from the moment of last CAR testing) the number of CAR was reduced when compared with the value registered before kindling by 35.3% (р<0.05) and at the same time was reduced when compared with the rats in control group by 23.4% (р<0.05). The latency of CAR in this period was greater when compared with the initial level by 21.0% (р<0.05). Repeated session of CAR precipitation performed during four days induced the increase of the number of CAR and shortening of their latency, which did not differ with their value from intial ones (p>0.05).
Conclusions. PTZ-induced kindling causes deterioration of CAR working out both in the early and postponed periods of kinlding. PTZ-induced model of kindling might be used as such one which corresponds to cognitive functions disturbances under conditions of chronic brain epileptization.