Newly Established Low Seizure Susceptible and Seizure-Prone Inbred Strains of Mongolian Gerbil

Two inbred strains of the Mongolian gerbil with different phenotypes in seizure behaviour and coat color were newly established. LSAG/Nu has low seizure susceptibility and albino phenotypes, whereas SPBG/Nu has seizure-prone and black coat color phenotypes. LSAG was compared with SPBG as to seizure incidence and grade. Mean ages at seizure onset of LSAG and SPBG were 6 and 3 months, respectively. Seizure incidences in over 9 months old LSAG and SPBG gerbils were 37.3% (66/177) and 95.2% (118/124), respectively. LSAG has a significantly lower incidence (p<0.001) and grade (p<0.001) of seizures than SPBG. Only a few seizing LSAG gerbils exhibited myoclonus to tonic-clonic seizure progression. These results suggest that LSAG has some mechanisms which delay the onset of seizures and prevent them from becoming serious. Both strains of gerbils can be expected to be useful animal models for the study of human idiopathic generalized epilepsy.