Interacción de focos penicilínicos simétricos corticales durante la depresión propagada de Leao.

Abstract

The effect of several unilateral Cortical Spreading Depressions of Leao (SD) on each hemisphere was observed in 17 white albino rats with symmetrical penicillin epileptic foci provoked in both sensory motor areas of the cerebral cortex with the aim of obtaining a better understanding of the facilitating or inhibitory interaction between two symmetrical epileptogenic lesions. The frequency variations recorded from the remanent focus during each SD were taken as a frame of reference for the changes effected. Analyzed as a whole, the data obtained during SD showed an increase in duration of the mean interval between epileptic spikes. Highly significant differences in intensity and duration of the modifications were found when the group of animals in which the primary focus was started in the left hemisphere was compared with the group in which it was started in the right hemispheres. In the first group the changes were more effective and prolonged, and the SD produced modifications similar to the remanent focus in both the left and right hemispheres. In the second group SD was less effective, and significant differences were found between the functional elimination of the left and right hemispheres. These inter hemisphere symmetrical and non-symmetrical interactions are discussed on the basis of simple and complex neuronal circuits connecting the hemispheres.