<P> Blood sugar levels are regulated by negative feedback in order to keep the body in balance . The levels of glucose in the blood are monitored by many tissues, but the cells in the pancreatic islets are among the most well understood and important . </P> <P> If the blood glucose level falls to dangerous levels (as during very heavy exercise or lack of food for extended periods), the alpha cells of the pancreas release glucagon, a hormone whose effects on liver cells act to increase blood glucose levels . They convert glycogen into glucose (this process is called glycogenolysis). The glucose is released into the bloodstream, increasing blood sugar . Hypoglycemia, the state of having low blood sugar, is treated by restoring the blood glucose level to normal by the ingestion or administration of dextrose or carbohydrate foods . It is often self - diagnosed and self - medicated orally by the ingestion of balanced meals . In more severe circumstances, it is treated by injection or infusion of glucagon . </P> <P> When levels of blood sugar rise, whether as a result of glycogen conversion, or from digestion of a meal, a different hormone is released from beta cells found in the Islets of Langerhans in the pancreas . This hormone, insulin, causes the liver to convert more glucose into glycogen (this process is called glycogenesis), and to force about 2 / 3 of body cells (primarily muscle and fat tissue cells) to take up glucose from the blood through the GLUT4 transporter, thus decreasing blood sugar . When insulin binds to the receptors on the cell surface, vesicles containing the GLUT4 transporters come to the plasma membrane and fuse together by the process of endocytosis, thus enabling a facilitated diffusion of glucose into the cell . As soon as the glucose enters the cell, it is phosphorylated into Glucose - 6 - Phosphate in order to preserve the concentration gradient so glucose will continue to enter the cell . Insulin also provides signals to several other body systems, and is the chief regulator of metabolic control in humans . </P> <P> There are also several other causes for an increase in blood sugar levels . Among them are the' stress' hormones such as epinephrine (also known as adrenaline), several of the steroids, infections, trauma, and of course, the ingestion of food . </P>

Insulin is released in response to low blood glucose levels