[Experimental study on splenomegaly after partial hepatectomy].

Abstract

Using 70% hepatectomized rat, morphological and functional changes of the spleen after partial hepatectomy were investigated. The results were as follows; 1. The weight of the spleen was maximum on the 7th and 10th day after partial hepatectomy and still high on the 14th day. There was no definite relationship between the weight of the spleen and the portal pressure. 2. Histologically and morphometrically, there was neither congestion nor enlargement in the red pulp after hepatectomy. Until the 3rd day after hepatectomy, the white pulp was developed. From the second day through the 14th day the marginal zone was enlarged. 3. The incorporation of 3H-thymidine into DNA of the spleen cells increased from the first day through the 7th day after hepatectomy. By autoradiography the labeled cells were mainly large mononuclear cells. 4. Both macrophages phagocytizing carbon particles in the red pulp and endogenous peroxidase-positive macrophages in the marginal zone were increased on the third day but not on the 7th day after hepatectomy. 5. Studied by immunohistochemistry with monoclonal antibodies, both T and B cells in the spleen were increased after hepatectomy. 1 and 3 days after hepatectomy T cell zone was predominant, but 7 days after hepatectomy B cell zone was predominant. Most of cells in the marginal zone were B cells and they were increased on the 7th day after hepatectomy. These results suggest that the splenomegaly after 70% hepatectomy is due to not only portal congestion or increase of macrophages but increase of lymphocytes.