Glucose Some glucose is converted to lactic acid by astrocytes, which is then utilized as an energy source by brain cells; some glucose is used by intestinal cells and red blood cells, while the rest reaches the liver, adipose tissue and muscle cells, where it is absorbed and stored as glycogen (under the influence of insulin). Liver cell glycogen can be converted to glucose and returned to the blood when insulin is low or absent; muscle cell glycogen is not returned to the blood because of a lack of enzymes. In fat cells, glucose is used to power reactions that synthesize
Stress in early childhood the skin and gut. This allows a sufficient amount of blood to access the brain and muscles. Also, epinephrine initiates the breakdown of glycogen in the liver, in turn increasing blood glucose levels. This energy source allows humans to enact defensive responses due to stress. In the human body, the steps that lead to the release of glucocorticoids such as cortisol begin with the release of corticotropin releasing hormone (CRH) and arginine vasopressin (AVP). These hormones travel through the blood vessels to the anterior pituitary gland of the brain. At this location, adrenocorticotropic hormone (ACTH) is released. ACTH binds to