Why is Glucose Control so Important?
In the fasting state, the suppression of insulin production and stimulation of glucagon production control the concentration of blood glucose. These processes allow the liver to mobilize glucose from its glycogen stores and synthesize glucose from amino acids and pyruvate (gluconeogenesis). In addition, when insulin levels are low, the uptake of glucose by muscle is minimized, and adipocytes release free fatty acids. This homeostatic mechanism effects a stable plasma glucose level in the fasting state so that the brain, which has no energy stores, has a sufficient supply of nutrients for normal activity.
In the fed state, insulin is released in two phases. The first phase, a short, small burst released on food intake or an increase in plasma glucose concentration, preempts and decreases the postprandial glucose elevation. Later, a more sustained, second-phase insulin release directly proportional to the plasma glucose elevation occurs. In response to this biphasic release of insulin, the liver takes up glucose, converting it to glycogen (animal starch). The muscle and adipose tissues also take up glucose, storing it as glycogen and triglycerides, respectively. Furthermore, the production of free fatty acids in adipocytes is suppressed. The loss of first-phase insulin release has adverse metabolic and physiologic consequences, even if the second-phase release is adequate or even excessive.
South Med J. 2001;94(8) © 2001 Lippincott Williams & Wilkins
Cite this: Importance of Postprandial Glucose Control - Medscape - Aug 01, 2001.