BDNF and Thrombocytosis: Increased BDNF in response to hyperthermia may be mediated through multiple mechanisms, including increased in shear stress, stimulating BDNF release by endothelial cells and platelets [18, 19]; an increase in the permeability of the blood-brain-barrier with an increase in body temperature, increasing the contribution of BDNF from the brain [11]; or a sympathetic activation-mediated increase in the release of BDNF containing platelets from the spleen (thrombocytosis) [20].