Insulin signal transduction pathway is secreted after glucose enters the beta cell and that triggers several other processes in a chain reaction. While insulin is secreted by the pancreas to lower blood glucose levels, glucagon is secreted to raise blood glucose levels. This is why glucagon has been known for decades as a counter-regulatory hormone. When blood glucose levels are low, the pancreas secretes glucagon, which in turn causes the liver to convert stored glycogen polymers into glucose monomers, which is then released into the blood. This process is called glycogenolysis. Liver cells, or hepatocytes, have glucagon receptors which allow for glucagon to attach
Insulin analog the yeast genome, and the yeast expressed the insulin analogue, which was then harvested from a bioreactor. This analogue also prevents the formation of hexamers, to create a faster acting insulin. It is approved for use in CSII pumps and Flexpen, Novopen delivery devices for subcutaneous injection. Glulisine is rapid acting insulin analog from Sanofi-Aventis, approved for use with a regular syringe, in an insulin pump. Standard syringe delivery is also an option. It is sold under the name Apidra. The FDA-approved label states that it differs from regular human insulin by its "rapid onset and shorter duration of action".