Motion picture acquisition and analysis of microcirculation in septic model rats

Microcirculation plays an important role by supplying oxygen and nutrients to maintain our lives. It is known that, as pathogenesis of sepsis, the microcirculation is impaired at the early stage of sepsis. In this case, it is expected that thrombomodulin alfa (TM alfa) works for the recovery of microcirculation. Direct observation of the impairment and recovery of microcirculation related to sepsis may give us clear understanding of those phenomena. In this study, we conducted experiments to observe microcirculation of septic model rats with an optical system. In these experiments, by attaching a chamber to the back of each rat, the same region of the microcirculation was consecutively monitored. Then, these rats were divided into three groups: control model rats (sham group), septic model rats (diseased group), and septic model rats to which TM alfa was administered (treated group). Each group includes five rats. In the diseased group smaller vessels disappeared and larger vessels became thinner. On the other hand, the treated group showed at first the degradation of microcirculation then the recovery. This may indicate effectiveness of TM alfa. We also estimated the blood velocity and blood vessel diameter from the acquired motion pictures to evaluate condition of the microcirculation. As a result, we quantitatively confirmed while blood velocity and blood vessel diameter of the diseased group decreased, that of the treated group decreased and then recovered. It should be noted that the set of motion pictures obtained in these experiments has potentially useful information for further analysis and is to be open to relevant researchers.