It is readily assumed that acute bleeding would cause changes in the speed of general circulation and in the circulation of bone marrow blood, and that such a change of bone marrow blood circulation would largely effect the mobilization of bone marrow depot blood cells. INOUE and Prof. HIRAKI have pointed out that the acceleration or inhibition of bone marrow circulation accompanied by the contraction or dilation on the nutricia vessels constitutes an important factor in accelerating or inhibiting the mobilization of bone marrow blood cells.
From this account, the results obtained through the experiments described in Part 1 have been reviewed, and the effect of bleeding upon the blood circulation in the bone marrow and the general circulation time has been re-examined through the thiasin method and the STEWART's method. The results are as follows: 1) The blood flow curve in the bone marrow taken by means of the thiasin method reached its peak within an hour after the bleeding. The curve taken at the 30 miuutes period before and after reaching its peak showed a shift to the left, indicating an acceleration of the blood flow. 2) The circulation time in the bone marrow was shortened, with its peak an hour after the bleeding, the values at 30 minutes before and after the peak showing various degrees of shortened time. 3) The pulmonary and systemic circulation time was shortened with its peak an hour after the bleeding, the values at 30 minutes before and after the peak showing various degrees of shortened time. 4) These observations suggest the events which take place in the marrow in the course of one to two hours after hemorrhage. The increase of blood cells in V. nutricia femoris was caused by mobilization of depot blood cells in the sinusoid. This mobilization was brought about by the shortening of the intramedullary circulation time associated with that of the general circulation time. Dilation and contraction of nutricia vessels following bleeding is only of secondary significance.