ABSTRACT

Sensitivity to febrile seizures was investigated in Wistar Albino Glaxo/Rijswijk (WAG/Rij) rats in the early life before spike and wave discharges occurred.

Wistar albino (n=7) and WAG/Rij (n=5) rat pups (21-22 days old) were exposed to warm water bath of 45 °C once every other day for a total of ten times to induce febrile seizures. The rats were kept in warm water for a maximum of four minutes or till the onset of seizures and body temperature was measured with the use of a rectal probe before the bath and at the onset of seizures. The latency and duration of seizures were recorded and the severity of seizures was rated using a 0-4 point scale.

The severity of seizures were similar in both groups. The latency of febrile seizures in WAG/Rij rats was longer in all the seizures, being significantly prolonged in the first, second, and 7th to 10th seizures (p<0.05). The number of seizures was correlated with increased seizure duration in both groups, which was significant for the 6th to 10th seizures in the Wistar group, and for the 8th to 10th seizures in the WAG/Rij group (p<0.05). However, the duration of seizures did not differ significantly between the two groups.

The longer latency of febrile seizures observed in WAG/Rij rats may indicate the development of a resistance to seizures related with the limbic structure. GABAergic mechanisms may be responsible for this resistance.

Keywords: Body temperature, disease models, animal, epilepsy, absence/physiopathology/genetics, heat/adverse effects, latency period, rats, inbred strains; seizures, febrile/physiopathology