The Mongolian gerbil in experimental epilepsy

R. Bertorelli, M. Adami, E. Ongini

The Mongolian gerbil is recognized as a suitable experimental model for studying epileptiform seizures. About 10-20% of the gerbils provided by animal breeders show convulsions when placed in a new laboratory environment or handled for drug administration. In this review, the usefulness of the gerbil is critically evaluated on the basis of the literature available and our experience. Since gerbils often react with seizures in response to external stimuli we utilized a blast of compressed air. Seven gerbils were tested once weekly, for 15 consecutive weeks, and electroencephalographic (EEG) activity was recorded. When the animals were challenged by a blast of compressed air they developed seizures, but with varying intensity and frequency. In the first weeks the majority of gerbils did not show seizures but they began to be susceptible to the stimulus from the 5th or 6th week. Four out of 7 animals proceeded to more severe seizures, characterized by clonic-tonic components. The pattern of behavioral seizures was paralleled by changes in the EEG recording. Altogether, data available indicate that the gerbil model is interesting in ethological studies and may be useful for investigating the mechanisms underlying "spontaneous" seizures. In pharmacology, however, the model has some weaknesses which limit its application in the study of new and established antiepileptic drugs.