[The cortical EEG in the acallosal mouse].
The congenital absence of the corpus callosum has recently been found to occur among some mice of the ddN strain in our laboratory. Morphologically, the absence of corpus callosum was classified into two types. One was complete agenesis of corpus callosum, and the other revealed partial agenesis (genu or splenium, or both). In this experiment, the differences of cortical EEG spectral characteristics were studied on the normal, hypogenesis and acallosal mice. A total of 75 male and female adult mice were used. Under light ether anesthesia, five stainless steel electrodes (0.29 mm) were implanted stereotaxically in the bilateral cerebral cortex and cerebellum at a depth of 1.0 mm. After one week recovery period, the correlations of EEG of five combinations, such as homotopic anterior vs. posterior, left vs. right hemispheres, crossed contralateral, and homotopic anterior and posterior to the reference electrode, were analysed with a signal processor. In the complete acallosal mice (n = 11), the correlation coefficients were significantly lower (p less than 0.05), in the crossed contralateral, left vs. right hemispheres, and homotopic posterior to reference. In the hypogenesis of corpus callosum (n = 7), however, they were no significant differences in the correlation compared with normal mice (n = 57). At the end of experiment, the brain was removed and fixed with 10% formalin, then it was cut in half along the midsagittal plane. The midsagittal section was used to examine an outline of the corpus callosum.
Okada
Y
Y
Department of Physical Education, Faculty of Education, Kagawa University, Takamatsu-city, Japan.
Negi
T
T
Hori
Y
Y
Murakami
T H
TH
D061085:Agenesis of Corpus Callosum; D000818:Animals; D002531:Cerebellum / Q000502:physiology; D002540:Cerebral Cortex / Q000502:physiology; D004567:Electrodes, Implanted; D004569:Electroencephalography; D005260:Female; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains