Estimated regional blood flow by rubidium 86 distribution during arousal from hibernation.

BULLARD, ROBERT W., AND GORDON E. FUNKHOUSER. ES& mated regional blood J-low by rubidium 86 distribution during arousal from hibernahn. Am. J. Physiol. 203(2) : 266-270. I 962 .-The local organ or tissue blood flows during the process of arousal from hibernation have been estimated in the 13-lined ground squirrel by the Sapirstein method, which consists of the measurement of the regional distribution of injected rubidium 86. The studies demonstrated that during arousal there is a confinement of blood flow to the thoracic regions. After the heart rate has attained IOO beats/min, blood flow increases to the anterior portions of the animal. At the arousal level characterized by a heart rate of 200 beats/min, blood flow to anterior and thoracic tissue had attained levels almost equal to control flows. Posterior tissue flows were still much lower than control flows. The centralization of blood flow to thoracic and anterior tissues did not occur in the rat in the hypothermic state. process. Since completion of our studies a report by Johansen (5) has appeared in which fractional distribution of injected rubidium 86 was similarly measured in the arousing and awake arctic ground squirrel (Spermophilus undulatus).