Physiology, Glucose Transporter Type 4

Excerpt

Among the numerous homeostatic events maintained by the human body, the blood glucose level is a significant physiologic aspect under persistent tight regulation. Glucose is an essential energy source that requires careful regulation within the body as both too much or too little glucose can cause detrimental effects. Blood glucose level is impacted by carbohydrate ingestion and regulated by insulin. Insulin regulates peripheral glucose uptake and glucose production within the liver — a family of five transmembrane proteins, known as GLUT, transport glucose via facilitated diffusion across the cell plasma membrane. They differ in kinetics and tissue distribution. The primary regulatory mechanism by which glucose uptake takes place is via insulin-stimulated transport of glucose into skeletal muscle and adipose tissue, primarily mediated by glucose transporter protein type-4 (GLUT4). GLUT4 is a key component in glucose homeostasis and the removal of glucose from circulation.