猫ヘモバルトネラ症に関する研究 : V. ヘモバルトネラ感染猫における脾の役割

抄録

The role of the spleen in feline haemobartonellosis was studied experimentally in 19 cats. The relationship between parasitemia and hematocrit (Ht) value, and the site of sequcstration in ⁵¹Cr-labeled parasitized erythrocytes were mainly examined in both splenectomized and non-splenectomized cats. In splenectomized cats the Ht value showed no significant changes in the early stage of infection in spite of the appearance of Haemobartonella felis on erythrocytes. In cats with the spleen intact it showed remarkable changes corresponding to the appearance and disappearance of the organism on erythrocytes during the experimental period. The splenic radioactivity of infected cats was six times as high as that of normal cats even in the early stage of infection. It increased markedly according to an increase in number of organisms appearing on erythrocytes. The hepatic and pulmonary radioactivity of infected cats showed only a slight or moderate increase in the severe stage of infection. On the contrary, the radioactivity of the organs examined in splenectomized cats did not increase significantly in the early stage of infection, although the radioactivity of liver, lung and bone marrow in these cats was two to three times as high as that in control animals in the severe stage of infection. In addition, parasitemia persisted apparently for a longer time in splenectomized cats than in cats with the spleen intact. From these results it is assumed that parasitized eryrthrocytes in cats infected with H. felis may be sequestrated mainly by the spleen and that the organism may be removed from host cells, without destroying the same cells in the spleen.