How would blood glucose levels be lowered upon becoming too high?

The high concentration of glucose in the blood is detected by the pancreas. Beta cells in the pancreas secrete insulin and the alpha cells cease production of glucagon. The insulin binds to specific receptors on liver and muscle cell membranes and increases their permeability to glucose. Therefore cells take up more glucose, lowering the concentration of glucose in the blood. Additionally, insulin activates enzymes responsible for glycogenesis, which is the converison of glucose to glycogen. Increased glycogenesis means decreased glucose levels. Finally, insulin increases rate of respiration so more glucose is used up and converted to energy, carbon dioxide and water.