Insulin and Glucose Insulin is a hormone which is produced by the pancreas. When you eat, and digestion begins, glucose from the food you've just eaten enters the blood. The glucose in the blood signals the pancreas to produce insulin. The insulin attaches to the glucose and carries it from the blood into the muscle, where it can be used for fuel. As the insulin carries glucose into the muscle the blood sugar level drops.
Some glucose is carried into the liver and stored there in the form of glycogen.
When the blood sugar level falls between meals the liver converts glycogen to glucose and releases it back into the bloodstream to be used as fuel and to keep the blood sugar from falling too low. When food is eaten and the blood sugar rises, causing insulin to be released into the blood it signals the liver to stop converting glycogen into glucose, and to begin drawing the excess glucose from the blood to rebuild its glycogen stores. Each cell is surrounded by a membrane, called the sarcolemma. The sarcolemma is the part of the muscle which contracts. The defect in HypoKPP is in a specific voltage-gated ion channel, depending on the mutation.