[Audiogenic seizures in rats of different genetic strains]

The temporal parameters of audiogenic seizures were compared in rats of different genetic strains (KM, Wistar, WAG/Rij, and GK). The probability of the origin of audiogenic fits was defined in each of the strains. It was found out that in Wistar, WAG/Rij, and GK rats the audiogenic fits developed as a double-wave pattern. In these strains the seizure intensity and their temporal parameters were the same but considerably differed from the intensive fits in KM rats, which developed as a one-wave pattern. The duration of the inhibitory pause between the first and the second wave in a double-wave fit was extremely stable, which could result from the spreading depression in one of the subcortical nuclei. Frequency spectra were compared of different kinds of stimuli applied for the audiogenic testing. Seizures were more easily provoked by the ultrasound signals with a complex structure. The resemblance is discussed between such signals and the natural communicative acoustic signals of rats as well as a possible role of emotional factor in the development of the audiogenic seizures.