THE DYNAMICS OF THE PHENOTYPICALLY AND GE NOTYPICALLY DETERMINED HIGHCONVULSIVE ACTIVITY OF THE BRAIN IN INTRACEREBRAL ALLOTRANSPLANTATIONOF EMBRYONAL NERVOUS-TISSUE

Experiments were made on rats of two lines during 120-140 days. A stud y was made of the effect of transplanting the embryonal hippocamp tiss ue and the septum (E 18) on the phenotypically (mechanical destruction in Wistar rats of the areas CA1 and CA4 of the fields of the hippocam p and dentate gyrus) and genotypically (Krushinsky-Molodkina rats, all responding to graded acoustic stimulations(86 dB) by audiogenic convu lsive fits) determined high convulsive activity of the brain. It has b een shown that from days 4-6, in 19 out of 23 Wistar rats, the transpl antation was followed by a steady increase of the threshold of convuls ive activity. As to the threshold of convulsive activity in K-M rats, it was affected by the transplantation to a slightly less measure. Out of 17 K-M rats, 9 stopped reacting to acoustic stimulations by audiog enic convulsive fits from days 39-44. In 5 more animals, convulsive fi ts failed to occur after every acoustic stimulation, the duration of t he clonic and tonic phases of convulsive fit and the duration of the p ostparoxysmal motor excitation declined.