THE RELATION OF THE SPLEEN TO BLOOD DESTRUCTION AND REGENERATION AND TO HEMOLYTIC JAUNDICE : XIV. CHANGES IN THE BLOOD FOLLOWING DIVERSION OF THE SPLENIC BLOOD FROM THE LIVER. A CONTROL STUDY OF THE EFFECTS OF SPLENECTOMY.

1. In dogs whose splenic veins have been ligated or transplanted into the inferior vena cava, or in which an Eck fistula has been made, an anemia occurs which resembles that following splenectomy and shows the same general variation in degree and duration. 2. The resistance of the red cells to hypotonic salt solution is quickly increased, sometimes coincident with and sometimes preceding the anemia. As a rule, it gradually returns to normal in about the same length of time as it takes the anemia to disappear, but may remain increased for longer periods. 3. There is an initial leukocytosis, involving at first the polymorphonuclear leucocytes and transitional cells. As the total leukocytosis diminishes there is both a relative and actual increase of small lymphocytes and usually of eosinophils. This may either be temporary or last during the rest of the period of observation and differs from the ordinary postoperative leukocytosis. 4. Ligation of the splenic vein is followed by considerable atrophy of the spleen, but not by necrosis or thrombosis. There is rarely adequate new vein formation. The other operations cause little or no change in the spleen. 5. Whether the disturbances as described are due to the loss of a certain volume of blood to the liver, or, as has been previously suggested, to the loss of a splenic hormone, it is impossible to say. If the former is true, the method of production of the anemia still remains unexplained. It is evident, furthermore, that the latter theory has also no value unless it is assumed that this hormone must be activated by passage through the liver.