[The long-term memory and learning capacity of rats with high brain seizure activity after an embryonic nerve tissue allograft].

Fragments of the embryonic hippocampus, septum, cerebellum and substantia nigra were grafted into the lesioned brain areas of 151 animals with phenotypical (bilateral destruction of the CA1 and CA4 hippocampal areas or the basolateral amygdalar regions in Wistar rats) and genotypic (in Krushinskiĭ-Molodkina strain) high seizure readiness. The parameters of long-term memory were improved after embryonic septal and cerebellar graftings, normalized after embryonic hippocampal graftings and were not improved after embryonic nigral graftings in both strains. Learning ability of the animals of both the strains with ceased audiogenic seizures was kept at the control level after the transplantation of embryonic tissue from the different brain areas.

[Threshold of sensitivity to epileptiform stimulus in intracerebral allotransplantation of embryonal nerve tissue of varying ergetics].

Effect of intracerebral allotransplantation of neocortex, hippocampus, septum, cerebellum, substantia nigra embryonic nerve tissue have been studied in white non-inbred, Wistar and Krushinski-Molodkina rats with phenotypically (portal destruction of hippocampus, gyrus serratus, corpus amygdaloideum and cerebral hypoxia) and genotypically conditioned by the low threshold of convulsive cerebral activity (TCCA). In focal cerebral affection transplants with monoergic neurones increase TCCA, while polyergic neurones of embryonic neocortex increase TCCA in diffuse cerebral affection. Phenotypically conditioned low TCCA increases in 4-6 days after transplantation and genotypically one--in 39-44 days because of the more complicated mechanisms of cerebral epileptization.