Abstract
In our Department of Pathology, Y. Kato reported that the blockade by gluey matters to the reticuloendothelial system of the adult rabbit furnishes a favourable condition to the infection of the Japanese encephalitis virus (Nakayama strain) and makes the invasion and propagation of virus easier by reducing the resistance of the rabbit to the virus.
Recently, the author succeeded in the return inoculations into mice successively, and reached the following conclusions. The results are reported from the clinical and pathological-histological point of view.
1. The amity of the Japanese encephalitis virus (Nakayama strain) inoculated into the rabbit to the brain-tissue becomes lower for a short period of time, but this affinity is recovered by successive mouse panages.
2. The svccesseive mouse pascages do not exercise big influence on the obstruction of circulation of the blood and the diffuse proliferation of glia cells.
3. The injuries to the tissue, the degeneration of ganglion cells and the formation of small nodules of gliacells tend to increase by the serccesive mouse passages.
4. The following is the author's opinion on the mice highly susceptible to the Japanese encephalitis virus : When a mouse becomes infected with the virus, loasening of the tissue, demyelinization, vecrosis and formation of small nodules of gliacells are seen as corrective and reactive functions against the injurious function of the virus to the tissue. The abone reactine funation possesses a defending effect against the virus in the diffusely proliferating gliacells.
5. In the present experiments, humidity (43%-94% in-door) did not exercise any obvious influence on the mice of appearance of these changes, but temperature (6°C⋅30°C in-door) affested the results to a considerable degree. Specifically, when the room temperature exceeded 10°C, the mice was found higher, therefore, the stability of these results were recognized.
