THE POSTNATAL GENESIS OF CEREBELLAR DEFECTS IN THE X-IRRADIATED MOUSE (in German)
The postnatal genesis of cerebellar defects in irradiated mice was studied. The experimental animals received a dose of 800 r of x radiation on the day of birth. At only four hours after irradiation, numerous pyknotic cells were observed in the granular layer and mantel zone. The embryonal granular layer seemed to be especially sensitive to radiation, for only a few cells of this stratum survived the radiation treatment. The radiation defects of the granular' layer and mantel zone lead to severe histotectogenetic derangements in the cortex: the structure of the stratum granulosum internum did not develop further. The Purkinje cells were distributed heterotopically over the entire cortex, without formation of a typical molecular stratum. Extending from small foci in several lobes (posterior lobe, cerebellar hemispheres) surviving embryonal granular cells initiated the repopulation of the embryonal granular layer. In this way normalization of the histogenetic processes was effected in these regions. The migratory cells from the partially regenerated embryonal granular layer produced an incomplete repair of the cortical radiation damage. The reparative processes resulted only from the embryonal granular layer. In the cerebellar lobes where the granular layer is not regenerated after the radiation insult the histotectonic organization of the cortex was generally unchanged. The Purkinje cells, the cerebellar nucleus, the choroid plexus, as well as the cerebellar brachia showed no changes, since they were essentially differentiated before the irradiation. Possible radiation injuries to the glia and the cerebellar medula or nerve fibers were not studied. The effect of x radiation on lobulation of the cerebellum was studied. Development of the cerebellum stopped several days after the radiation exposure. Lobulation of the extraventricular surface made no additional progress. All sulci and lobuli were absent. In the vermis and hemispheres shallow sagittally oriented grooves appeared during the repair period. (BBB)
- Research Organization:
- Universitat, Halle-Wittenberg, Ger.
- NSA Number:
- NSA-18-011740
- OSTI ID:
- 4126668
- Journal Information:
- Journal fuer Hirnforschung (East Germany), Journal Name: Journal fuer Hirnforschung (East Germany) Vol. Vol: 5; ISSN JOHIA
- Country of Publication:
- Country unknown/Code not available
- Language:
- German
Similar Records
Structural disorganization of rat cerebellar cortex induced by exposure to gamma radiation at the differentiation stage
Effect of 2,450 MHz microwave radiation on the development of the rat brain