[Intracortical synchronization of the epileptiform field potentials at different stages of ultrastructural reorganizations in neuronally isolates island in rats].
A temporal delay (parameter of synchronization) between the incidence of epileptiform discharges in cortical sited located at a distance of 4 mm from each other was studied in rat intact cortex and neuronally isolated cortical slab using the cross-correlation function. Experiments were carried out at different stages of axonal sprouting. By 30 days of isolation, a significant increase in the number of boutons in the V cortical layer coincided with a significant decrease in the delay, whereas a reduction of the number of boutons by 90 days corresponded to its increase. These findings convincingly testify that the newly formed boutons form a basis for increase in synchronization and thus affect the epileptogenesis. The results obtained in this work and literature data suggest that under pathological conditions large pyramids of the V layer form a neuronal network which provides exclusively cortical synchronization of epileptiform field potentials.
Marchenko
V G
VG
Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow. V_marchenko@hotmail.ru
Pasikov
N V
NV
Kositsyn
N S
NS
D000818:Animals; D002540:Cerebral Cortex / Q000503:physiopathology*; D003344:Cortical Synchronization / Q000295:instrumentation*; D004569:Electroencephalography; D004827:Epilepsy / Q000503:physiopathology*; D007839:Functional Laterality / Q000502:physiology; D009415:Nerve Net / Q000503:physiopathology; D009474:Neurons / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar