Blood Leukocytes and Platelets of Little Ground Squirrels (Spermophilus pygmaeus Pall.) during Hibernation and Arousal

During the period of hibernation, mammals periodically go through cold (torpor) and warm (аrousal) phases. Previously, a sharp decrease in the levels of blood leukocytes and platelets in the torpid state was found; however, the dynamics of their changes during аrousal remains unknown. We studied the content and composition of circulating cells of the little ground squirrel during аrousal. The number of all types of leukocytes and platelets in a torpid state is significantly reduced. The restoration of leukocyte level in the blood during аrousal occurs in two phases: fast (Tb 10–20^○C) and slow (Tb 20–37^○C). Unlike other cell types, the content of neutrophils after temperature restoration remains below the control. During аrousal, the platelet level increases linearly in the range of Tb 10–30^○C; at the same time, no normalization of the P-LCR parameter occurs.