Mechanisms of disrupting the microcirculation in the brain during deep hypothermia development

摘要

The number of the acts of leukocyte adhesion per unit of the vessel length was shown to increase gradually in the venous brain vessels during gradual cooling of the white rat from the body temperature in the rectum of approximately 37 to 13.5 +/- 0.2 degrees C. Upon a very deep hypothermia at the level of body temperature of 15 degrees C, the adhesion ofleukocytes to the walls of the brain microvessels gains a mass character. As the body temperature decreases to 13.5 +/- 0.2 degrees C, the respiration gets arrested. This coincides with an aspecially abrupt increase in the number of the acts of adhesion and with stretching the venules and smallest veins. The dynamics of these phenomena resembles the development of the mass adhesion of leukocytes during various kinds of hypoxia. There are reasons to believe that the adhesion of leukosytes during hypothermia disrupts the microcirculation and provokes the development of hypoxia in the cooled brain. nauk